drm/amd/powerplay: put VCN/JPEG into PG ungate state before dpm table setup(V3)

As VCN related dpm table setup needs VCN be in PG ungate state. Same logics
applies to JPEG.

V2: fix paste typo
V3: code cosmetic

Signed-off-by: Evan Quan <evan.quan@amd.com>
Tested-by: Matt Coffin <mcoffin13@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>