drm/radeon: convert to pmops

This is a pre-requisite for runtime pm on powerxpress systems.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --cc drivers/gpu/drm/radeon/radeon.h
Simple merge

diff --cc drivers/gpu/drm/radeon/radeon_device.c
Simple merge

diff --cc drivers/gpu/drm/radeon/radeon_drv.c
Simple merge