[3.12] gh-128916: Do not set `SO_REUSEPORT` on non-`AF_INET*` sockets (GH-128933...

[3.12] gh-128916: Do not set `SO_REUSEPORT` on non-`AF_INET*` sockets (GH-128933) (#128970)

gh-128916: Do not set `SO_REUSEPORT` on non-`AF_INET*` sockets (GH-128933)

* gh-128916: Do not set `SO_REUSEPORT` on non-`AF_INET*` sockets

Do not attempt to set ``SO_REUSEPORT`` on sockets of address familifies other
than ``AF_INET`` and ``AF_INET6``, as it is meaningless with these address
families, and the call with fail with Linux kernel 6.12.9 and newer.

* Apply suggestions from code review

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(cherry picked from commit 3829104ab412a47bf3f36b8c133c886d2cc9a6d4)

Co-authored-by: Michał Górny <mgorny@gentoo.org>
Co-authored-by: Vinay Sajip <vinay_sajip@yahoo.co.uk>