Nftables: Support xt_addrtype match.

Added:
- `xt_addrtype` extension to match packets based on their address type
   (LOCAL/UNICAST/...) by querying FIB/routing table.
- XTAddrtypeInfo (rev0) and XTAddrtypeInfoV1 (rev1) ABI support.
- Unit test and syscall tests.

Ref: net/netfilter/xt_addrtype.c
PiperOrigin-RevId: 963909387