Move SysConf to Core

It's not common code that could be reused for, say, Citra;
it's absolutely specific to Wii emulation and only used by the Dolphin
core, so let's move it there.

Another reason for doing this is to avoid having Common depend on Core.

Source/Core/Core/WiiRoot.cpp

@@ -11,11 +11,11 @@
 #include "Common/Logging/Log.h"
 #include "Common/NandPaths.h"
 #include "Common/StringUtil.h"
-#include "Common/SysConf.h"
 #include "Core/ConfigManager.h"
 #include "Core/IOS/IOS.h"
 #include "Core/Movie.h"
 #include "Core/NetPlayClient.h"
+#include "Core/SysConf.h"
 
 namespace Core
 {