mesa: skip redundant uniform updates for glUniform
Viewperf does a lot of redundant uniform updates - 60-80% in some tests. Those are sometimes the only state changes between draw calls. This improves performance by 33% in one viewperf subtest. If you are worried about CPU overhead in the non-redundant case, glthread is the solution. Reviewed-by:Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com> Part-of: <mesa/mesa!6946>