netfilter: remove unused "config IP_NF_QUEUE"

Kconfig symbol IP_NF_QUEUE is unused since commit
d16cf20e2f2f13411eece7f7fb72c17d141c4a84 ("netfilter: remove ip_queue
support"). Let's remove it too.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>