tools: ynl: stop using mnl socket helpers

Most libmnl socket helpers can be replaced by direct calls to
the underlying libc API. We need portid, the netlink manpage
suggests we bind() address of zero.

Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20240227223032.1835527-14-kuba@kernel.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>