qcacmn: fix peer ref counter unexpected increasement

Host will drop the RX data that introduced in change
"add counters for sa_idx invalid issue", the related peer
has done ref_cnt + 1, but there is no peer ref_cnt -1 accordingly.
peer ref_cnt increase unexpected, panic happened when rmmod at last.

add the peer ref_cnt decrease operation.

Change-Id: Ie6bc5b57560a93c5f21431838b7bcb1140abfec5
CRs-Fixed: 2454468

dp/wifi3.0/dp_rx.c

@@ -2152,6 +2152,7 @@ done:
 				qdf_nbuf_free(nbuf);
 				nbuf = next;
 				DP_STATS_INC(soc, rx.err.invalid_sa_da_idx, 1);
+				dp_peer_unref_del_find_by_id(peer);
 				continue;
 			}
 			/* WDS Source Port Learning */