qcacmn: set SRNG_FLUSH_EVENT if runtime suspended

During dp_tx_hw_enqueue writing into HW SRNG,
if devcie is already runtime suspended, set the
SRNG_FLUSH_EVENT, so that it will be flushed
as part of dp runtime resume callback.

Change-Id: I95e74844cf74eb4f73862da3da9d93422f1eea8c
CRs-Fixed: 2664660

dp/wifi3.0/dp_tx.c

@@ -1238,6 +1238,8 @@ ring_access_fail:
 				   RTPM_ID_DW_TX_HW_ENQUEUE);
 	} else {
 		dp_tx_hal_ring_access_end_reap(soc, hal_ring_hdl);
+		hal_srng_set_event(hal_ring_hdl, HAL_SRNG_FLUSH_EVENT);
+		hal_srng_inc_flush_cnt(hal_ring_hdl);
 	}
 
 	return status;