drm/amd/powerplay: bump the PPtable version supported

As the matching VBIOS is already ready. Also drop the
temporary workarounds applied before.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Feifei Xu <Feifei.Xu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>