netfilter: nft_log: fix coccinelle warnings

net/netfilter/nft_log.c:79:44-45: Unneeded semicolon

 Removes unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

CC: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>