SOC15_WAIT_ON_RREG's return value needn't always been handled by
caller. new design is to fix this kind of unused variable.
Signed-off-by: NJames Zhu <James.Zhu@amd.com>
Reported-by: Nkernel test robot <lkp@intel.com>
Acked-by: NLeo Liu <leo.liu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>