drm/amdgpu: enable mes v12 self test

1. fix available compute queue to use
2. enable mes v12 self test

Signed-off-by: Jack Xiao <Jack.Xiao@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>