Revert "KGSL: use simple governor only when enabled"

This reverts commit ff203ce868d16c34a43e8e8945ba6c8c97e56d8e.
Revert "added GPU O/C freq 487.5MHz"

This reverts commit 3e62bbca54022361bb4b2e44d9e76a867cd2194a.
Revert "added GPU O/C upto 533MHz"

This reverts commit ae7a3ef7c918584337426627a4291f7146cabd70.