drm/amd/pm: use pm_runtime_resume_and_get

Using pm_runtime_resume_and_get over pm_runtime_get_sync is recommended.

Tested-by: Mario Limonciello <[email protected]>
Reviewed-by: Kenneth Feng <[email protected]>
Signed-off-by: Pierre-Eric Pelloux-Prayer <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

Author: peppsac