netfilter: x_tables: set module owner for icmp(6) matches

nft_compat relies on xt_request_find_match to increment
refcount of the module that provides the match/target.

The (builtin) icmp matches did't set the module owner so it
was possible to rmmod ip(6)tables while icmp extensions were still in use.

Signed-off-by: Florian Westphal <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

net/ipv4/netfilter/ip_tables.c

···
 		.checkentry = icmp_checkentry,
 		.proto      = IPPROTO_ICMP,
 		.family     = NFPROTO_IPV4,
+		.me	    = THIS_MODULE,
 	},
 };
 

net/ipv6/netfilter/ip6_tables.c

···
 		.checkentry = icmp6_checkentry,
 		.proto      = IPPROTO_ICMPV6,
 		.family     = NFPROTO_IPV6,
+		.me	    = THIS_MODULE,
 	},
 };