ip: fix crash in "ip neigh show"

parse_rtattr() was using tb[] array without initializing it.

Based on patch by Balaji Punnuru <balaji_punnuru@cable.comcast.com>

function                                             old     new   delta
parse_rtattr                                          85     107     +22
print_route                                         1630    1617     -13
print_linkinfo                                       807     794     -13
iproute_get                                          835     822     -13
print_rule                                           680     665     -15
ll_remember_index                                    263     248     -15
print_addrinfo                                      1223    1197     -26
ipaddr_list_or_flush                                1253    1223     -30
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/7 up/down: 22/-125)          Total: -103 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/libiproute/ipaddress.c b/networking/libiproute/ipaddress.c
index 921ecf0..d7f8881 100644
--- a/networking/libiproute/ipaddress.c
+++ b/networking/libiproute/ipaddress.c
@@ -113,7 +113,7 @@
 	if (G_filter.up && !(ifi->ifi_flags & IFF_UP))
 		return 0;
 
-	memset(tb, 0, sizeof(tb));
+	//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
 	parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
 	if (tb[IFLA_IFNAME] == NULL) {
 		bb_error_msg("nil ifname");
@@ -227,7 +227,7 @@
 	if (G_filter.flushb && n->nlmsg_type != RTM_NEWADDR)
 		return 0;
 
-	memset(rta_tb, 0, sizeof(rta_tb));
+	//memset(rta_tb, 0, sizeof(rta_tb)); - parse_rtattr does this
 	parse_rtattr(rta_tb, IFA_MAX, IFA_RTA(ifa), n->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa)));
 
 	if (!rta_tb[IFA_LOCAL])
@@ -535,7 +535,7 @@
 					continue;
 				if (G_filter.pfx.family || G_filter.label) {
 					struct rtattr *tb[IFA_MAX+1];
-					memset(tb, 0, sizeof(tb));
+					//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
 					parse_rtattr(tb, IFA_MAX, IFA_RTA(ifa), IFA_PAYLOAD(n));
 					if (!tb[IFA_LOCAL])
 						tb[IFA_LOCAL] = tb[IFA_ADDRESS];