gsdx-debug: print an error on unsupported draw call

Typically GTA

plugins/GSdx/GSRendererHW.cpp

@@ -358,6 +358,11 @@ void GSRendererHW::Draw()
 
 	if(PRIM->TME)
 	{
+#ifdef ENABLE_OGL_DEBUG
+		if ((context->FRAME.Block() == context->TEX0.TBP0) && (m_vertex.next > 2)) {
+			GL_INS("ERROR: Source and Target are the same!");
+		}
+#endif
 		/*
 		
 		// m_tc->LookupSource will mess with the palette, should not, but we do this after, until it is sorted out