drm/amdgpu: add xcc index argument to soc15_grbm_select
To support grbm select for multiple XCD case.
v2: unify naming style
Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
authored by