qcacmn: Access msdu_len from struct cb to avoid cache miss

We are accessing nbuf_len field for every nbuf
and which causes cache hit as we are accessing
it not from 1st cache line. This field is present
in struct cb. Lets access it from here to avoid
cache miss.

Change-Id: I21a81d844a4cc755a0ca0c156bd3f4d5702fd913
CRs-fixed: 2449717

dp/wifi3.0/dp_rx.c

@@ -1390,7 +1390,7 @@ static void dp_rx_msdu_stats_update(struct dp_soc *soc,
 	uint32_t sgi, mcs, tid, nss, bw, reception_type, pkt_type;
 	struct dp_vdev *vdev = peer->vdev;
 	qdf_ether_header_t *eh;
-	uint16_t msdu_len = qdf_nbuf_len(nbuf);
+	uint16_t msdu_len = QDF_NBUF_CB_RX_PKT_LEN(nbuf);
 
 	peer_id = DP_PEER_METADATA_PEER_ID_GET(
 			       hal_rx_mpdu_peer_meta_data_get(rx_tlv_hdr));