Replace all include guard ifdefs with "#pragma once"

Source/Core/VideoCommon/VertexLoader_TextCoord.h

@@ -2,8 +2,7 @@
 // Licensed under GPLv2
 // Refer to the license.txt file included.
 
-#ifndef VERTEXLOADER_TEXCOORD_H
-#define VERTEXLOADER_TEXCOORD_H
+#pragma once
 
 #include "NativeVertexFormat.h"
 
@@ -24,5 +23,3 @@ public:
 	// It is important to synchronize tcIndex.
 	static TPipelineFunction GetDummyFunction();
 };
-
-#endif