OpenGL Renderer: More updates to the 3.2 Core Profile renderer to be …

…more cross-compatible with OpenGL ES 3.0.

- Add support for fixed locations in shaders for OpenGL 3.3 and later.
- The fog density table texture is now a 2D texture instead of a 1D texture.
- Fix a memory leak where the polygon state texture wasn't being deleted upon the destruction of the OpenGLRenderer object.

desmume/src/OGLRender.cpp

@@ -3044,6 +3044,13 @@ void OpenGLRenderer_1_2::DestroyFBOs()
 	OGLRef.fboClearImageID = 0;
 	OGLRef.fboFramebufferFlipID = 0;
 	OGLRef.fboRenderID = 0;
+	OGLRef.texCIColorID = 0;
+	OGLRef.texCIFogAttrID = 0;
+	OGLRef.texCIDepthStencilID = 0;
+	OGLRef.texGColorID = 0;
+	OGLRef.texGPolyID = 0;
+	OGLRef.texGFogAttrID = 0;
+	OGLRef.texGDepthStencilID = 0;
 
 	this->isFBOSupported = false;
 }