qcacld-3.0: p2p: Replace explicit comparison to NULL

Per the Linux Kernel coding style, as enforced by the kernel
checkpatch script, pointers should not be explicitly compared to
NULL. Therefore within p2p replace any such comparisons with logical
operations performed on the pointer itself.

Change-Id: I3f987cc2603bd3e4d41881db8c847046884d7e76
CRs-Fixed: 2418399

p2p/core/src/wlan_p2p_off_chan_tx.c

@@ -860,7 +860,7 @@ static QDF_STATUS p2p_packet_alloc(uint16_t size, void **data,
 			P2P_TX_PKT_MIN_HEADROOM, sizeof(uint32_t),
 			false);
 
-	if (nbuf != NULL) {
+	if (nbuf) {
 		qdf_nbuf_put_tail(nbuf, size);
 		qdf_nbuf_set_protocol(nbuf, ETH_P_CONTROL);
 		*ppPacket = nbuf;