to avoid reading wrong WPTR from doorbell in sriov vf, set
CP_HQD_PQ_DOORBELL_CONTROL.DOORBELL_MODE to 1 to read WPTR from MQD.
Signed-off-by: Zhigang Luo <Zhigang.Luo@amd.com>
Acked-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>