do only invalid hashes instead of all textures on loading

this is a hack, but only the gpu thread is allowed to call ogl commands
suggestion: create an unused texture cache, so we can move all textures there

Source/Core/VideoCommon/Src/TextureCacheBase.cpp

@@ -72,6 +72,18 @@ void TextureCache::Invalidate()
 	textures.clear();
 }
 
+// this function is dirty hack to work around a OGL bug.
+// it is only used on loading states. It will work for normal textures,
+// but for efb2ram, it wouldn't be checked. So there may be glitches on loading
+void TextureCache::InvalidateHashes()
+{
+	TexCache::iterator
+		iter = textures.begin(),
+		tcend = textures.end();
+	for (; iter != tcend; ++iter)
+		iter->second->hash = TEXHASH_INVALID;
+}
+
 TextureCache::~TextureCache()
 {
 	Invalidate();