qcacmn: Add NULL check for dp_pev

Currently, no NULL check is made for the value of dp_pev.
Adding a NULL check to avoid NULL dereference.

Change-Id: I2712b7e2fd53ba3a346878e73d2eedac161c5935
CRs-Fixed: 2955365

dp/wifi3.0/dp_rx.c

@@ -324,7 +324,13 @@ QDF_STATUS __dp_rx_buffers_replenish(struct dp_soc *dp_soc, uint32_t mac_id,
 
 	rxdma_srng = dp_rxdma_srng->hal_srng;
 
-	if (!rxdma_srng) {
+	if (qdf_unlikely(!dp_pdev)) {
+		dp_rx_err("%pK: pdev is null for mac_id = %d",
+			  dp_soc, mac_id);
+		return QDF_STATUS_E_FAILURE;
+	}
+
+	if (qdf_unlikely(!rxdma_srng)) {
 		dp_rx_debug("%pK: rxdma srng not initialized", dp_soc);
 		DP_STATS_INC(dp_pdev, replenish.rxdma_err, num_req_buffers);
 		return QDF_STATUS_E_FAILURE;
@@ -2290,6 +2296,12 @@ dp_pdev_rx_buffers_attach(struct dp_soc *dp_soc, uint32_t mac_id,
 	int sync_hw_ptr = 1;
 	uint32_t num_entries_avail;
 
+	if (qdf_unlikely(!dp_pdev)) {
+		dp_rx_err("%pK: pdev is null for mac_id = %d",
+			  dp_soc, mac_id);
+		return QDF_STATUS_E_FAILURE;
+	}
+
 	if (qdf_unlikely(!rxdma_srng)) {
 		DP_STATS_INC(dp_pdev, replenish.rxdma_err, num_req_buffers);
 		return QDF_STATUS_E_FAILURE;