drm/radeon: fix regression in dynpm due to multi-ring rework
drm/radeon: fix regression in dynpm due to multi-ring rework

Not all asics have all rings, so make sure the ring is ready
before attempting to check it in the dynpm work handler.

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=43367

Signed-off-by: Alex Deucher <08dc22c6156113f2deff178e35e3ed9b24d6af9e@amd.com>
Reviewed-by: Jerome Glisse <0620d428a1bd3756b1319066bf466b3b8be0b2b2@redhat.com>
Reviewed-by: Christian König <c7ea837d7a46effe4232b086213468b8b31643bf@amd.com>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs