qcacld-3.0: Add pointer sanity check for mac context

Add pointer sanity check for mac context in wma_send_peer_assoc_req
as cds_get_context may return Null for mac context

Change-Id: I75a54d728f2c276a9aeeb1ee7d8ea46180540ac8
CRs-Fixed: 2706149

core/wma/src/wma_dev_if.c

@@ -3693,6 +3693,10 @@ QDF_STATUS wma_send_peer_assoc_req(struct bss_params *add_bss)
 		WMA_LOGE("Invalid wma");
 		return QDF_STATUS_E_INVAL;
 	}
+	if (!mac) {
+		WMA_LOGE("Invalid mac context");
+		return QDF_STATUS_E_INVAL;
+	}
 
 	vdev_id = add_bss->staContext.smesessionId;