MAINTAINERS: netfilter: add irc channel

The community #netfilter IRC channel is now live on the libera.chat network
(https://libera.chat/).

CC: Arturo Borrero Gonzalez <arturo@netfilter.org>
Link: https://marc.info/?l=netfilter&m=162210948632717Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

MAINTAINERS

@@ -12657,6 +12657,7 @@ W:	http://www.netfilter.org/
 W:	http://www.iptables.org/
 W:	http://www.nftables.org/
 Q:	http://patchwork.ozlabs.org/project/netfilter-devel/list/
+C:	irc://irc.libera.chat/netfilter
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next.git
 F:	include/linux/netfilter*