qcacld-3.0: Do not overwrite session->nss with add_bss_rsp->nss

NSS value in ADD_BSS response indicates NSS of the connection, while session
NSS value indicates self NSS capability used by FW to dynamically switch to
higher NSS opportunistically. Hence do not overwrite session NSS with ADD BSS
response NSS as that would cause DUT to get stuck in 1x1 and not upgrade to 2x2
opportunistically.

Change-Id: Ie4849a1ccd645ef477a90afa09ef8172048e0a86
CRs-Fixed: 1090245

core/mac/src/pe/lim/lim_process_mlm_rsp_messages.c

@@ -2626,7 +2626,6 @@ void lim_process_mlm_add_bss_rsp(tpAniSirGlobal mac_ctx,
 		return;
 	}
 
-	session_entry->nss = add_bss_param->nss;
 	bss_type = session_entry->bssType;
 	/* update PE session Id */
 	mlm_start_cnf.sessionId = session_entry->peSessionId;