UPSTREAM: netfilter: nf_tables: Reject tables of unsupported family

commit f1082dd31fe461d482d69da2a8eccfeb7bf07ac2 upstream.

An nftables family is merely a hollow container, its family just a
number and such not reliant on compile-time options other than nftables
support itself. Add an artificial check so attempts at using a family
the kernel can't support fail as early as possible. This helps user
space detect kernels which lack e.g. NFPROTO_INET.

Bug: 321815738
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 25d1e7be85cf0a5afca5555f90e4609c40480ece)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I45b5c6f046e9156edf4c60bf5611367fe25f8ec9