materialsystem: fix color correction on non-windows systems( fixes #137 , #295 related )

materialsystem/CColorCorrection.cpp

@@ -82,7 +82,12 @@ void ColorCorrectionLookup_t::AllocTexture()
 	sprintf( name, "ColorCorrection - %p", m_Handle );
 
 	m_pColorCorrectionTexture = ITextureInternal::CreateProceduralTexture( name, TEXTURE_GROUP_OTHER,
-		COLOR_CORRECTION_TEXTURE_SIZE, COLOR_CORRECTION_TEXTURE_SIZE, COLOR_CORRECTION_TEXTURE_SIZE, IMAGE_FORMAT_BGRX8888,
+		COLOR_CORRECTION_TEXTURE_SIZE, COLOR_CORRECTION_TEXTURE_SIZE, COLOR_CORRECTION_TEXTURE_SIZE,
+#ifdef DX_TO_GL_ABSTRACTION
+		IMAGE_FORMAT_RGBA8888,
+#else
+		IMAGE_FORMAT_BGRX8888,
+#endif
 		TEXTUREFLAGS_NOMIP | TEXTUREFLAGS_NOLOD | TEXTUREFLAGS_SINGLECOPY | TEXTUREFLAGS_CLAMPS | 
 		TEXTUREFLAGS_CLAMPT | TEXTUREFLAGS_CLAMPU | TEXTUREFLAGS_NODEBUGOVERRIDE );