Support for routing table indices > 255

[tbottomparallel]

Would adding this feature cause a breaking change? Yes - it would require modifying neli::consts::rtnl::RtTable

Is your feature request related to a problem? Please describe. Yes - rtnetlink supports table id's up to 0xFFFFFFFF but RtTable::UnrecognizedConst(c_uchar) only supports up to u8::MAX. (see https://elixir.bootlin.com/linux/v6.10.8/source/include/uapi/linux/rtnetlink.h#L354)

For example, table 51820 is typically used by wireguard.

Describe the solution you'd like RtTable::UnrecognizedConst(u32) or a new enum variant allowing the full range of routing table id's.

Describe alternatives you've considered None: cannot construct neli::rtnl::Rtmsg message for tables with id > 255.

Additional context N/A