netfilter: update MAINTAINERS

It's been a while since Patrick has been suspended as coreteam member [1].
Update this file to remove him.

While at this, remove references to all foo-tables variants, given the
project hosts more than just that, eg. ipset, conntrack, ...

[1] https://marc.info/?l=netfilter-devel&m=146887464512702Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

MAINTAINERS

@@ -8579,9 +8579,8 @@ F:	Documentation/networking/s2io.txt
 F:	Documentation/networking/vxge.txt
 F:	drivers/net/ethernet/neterion/
 
-NETFILTER ({IP,IP6,ARP,EB,NF}TABLES)
+NETFILTER
 M:	Pablo Neira Ayuso <pablo@netfilter.org>
-M:	Patrick McHardy <kaber@trash.net>
 M:	Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
 L:	netfilter-devel@vger.kernel.org
 L:	coreteam@netfilter.org