Revert "gpu: enable slumber"

This reverts commit b99daf1a412c01798ff8a16bc0f511c8a2b95297.
Revert "fixed mdp4 overlay compile warnings"

This reverts commit 3b688b0f24f7ce2511f8ac2112e06e0d3db4abb5.
Revert "lowered GPU minimum freq and removed some GPU steps"

This reverts commit eba7e1e925507470f1383d9a05870382d29027ea.