treewide: convert GPLv2+ license info to SPDX tags

SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.

Source/Core/DolphinQt/QtUtils/AspectRatioWidget.cpp

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 // Based on:
 // https://stackoverflow.com/questions/30005540/keeping-the-aspect-ratio-of-a-sub-classed-qwidget-during-resize

Source/Core/DolphinQt/QtUtils/AspectRatioWidget.h

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/BlockUserInputFilter.cpp

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/BlockUserInputFilter.h"
 

Source/Core/DolphinQt/QtUtils/BlockUserInputFilter.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/DoubleClickEventFilter.cpp

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <QEvent>
 

Source/Core/DolphinQt/QtUtils/DoubleClickEventFilter.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/ElidedButton.cpp

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/ElidedButton.h"
 

Source/Core/DolphinQt/QtUtils/ElidedButton.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/FileOpenEventFilter.cpp

@@ -1,6 +1,5 @@
 // Copyright 2019 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <QFileOpenEvent>
 

Source/Core/DolphinQt/QtUtils/FileOpenEventFilter.h

@@ -1,6 +1,5 @@
 // Copyright 2019 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/ImageConverter.cpp

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/ImageConverter.h"
 

Source/Core/DolphinQt/QtUtils/ImageConverter.h

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/ModalMessageBox.cpp

@@ -1,6 +1,5 @@
 // Copyright 2019 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/ModalMessageBox.h"
 

Source/Core/DolphinQt/QtUtils/ModalMessageBox.h

@@ -1,6 +1,5 @@
 // Copyright 2019 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/QueueOnObject.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/RunOnObject.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/SignalDaemon.cpp

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/SignalDaemon.h"
 

Source/Core/DolphinQt/QtUtils/SignalDaemon.h

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/UTF8CodePointCountValidator.cpp

@@ -1,6 +1,5 @@
 // Copyright 2020 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/UTF8CodePointCountValidator.h"
 

Source/Core/DolphinQt/QtUtils/UTF8CodePointCountValidator.h

@@ -1,6 +1,5 @@
 // Copyright 2020 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/WinIconHelper.cpp

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/WinIconHelper.h"
 

Source/Core/DolphinQt/QtUtils/WinIconHelper.h

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/WindowActivationEventFilter.cpp

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <QEvent>
 #include <QObject>

Source/Core/DolphinQt/QtUtils/WindowActivationEventFilter.h

@@ -1,6 +1,5 @@
 // Copyright 2017 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 

Source/Core/DolphinQt/QtUtils/WrapInScrollArea.cpp

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "DolphinQt/QtUtils/WrapInScrollArea.h"
 

Source/Core/DolphinQt/QtUtils/WrapInScrollArea.h

@@ -1,6 +1,5 @@
 // Copyright 2018 Dolphin Emulator Project
-// Licensed under GPLv2+
-// Refer to the license.txt file included.
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once