staging: lustre: fix socklnd issues found by Klocwork Insight tool

Null pointer 'best_iface' that comes from line 802 may be
dereferenced at line 832.
Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4629
Reviewed-on: http://review.whamcloud.com/9386Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Isaac Huang <he.huang@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/klnds/socklnd/socklnd.c

@@ -804,6 +804,8 @@ ksocknal_select_ips(ksock_peer_t *peer, __u32 *peerips, int n_peerips)
 			ip = peer->ksnp_passive_ips[i];
 			best_iface = ksocknal_ip2iface(peer->ksnp_ni, ip);
 
+			/* peer passive ips are kept up to date */
+			LASSERT(best_iface);
 		} else {
 			/* choose a new interface */
 			LASSERT(i == peer->ksnp_n_passive_ips);
@@ -838,6 +840,8 @@ ksocknal_select_ips(ksock_peer_t *peer, __u32 *peerips, int n_peerips)
 				best_npeers = iface->ksni_npeers;
 			}
 
+			LASSERT(best_iface);
+
 			best_iface->ksni_npeers++;
 			ip = best_iface->ksni_ipaddr;
 			peer->ksnp_passive_ips[i] = ip;