bind(2): Lookup local address in current FIB if '*.bind_all_fibs' is active

When a protocol-specific 'bind_all_fibs' tunable is set to 0, a
listening socket will only receive traffic originating fro

bind(2): Lookup local address in current FIB if '*.bind_all_fibs' is active

When a protocol-specific 'bind_all_fibs' tunable is set to 0, a
listening socket will only receive traffic originating from the FIB
it was bound to. However, there are no checks to determine whether
an address exists in the target FIB when binding the socket, which can
lead to a situation where a socket and the address it was bound to
belong to different FIBs.

Prevent this footgun by looking up the requested address in the current
FIB if 'bind_all_fibs' is active and returning an error if the address
does not exist.

Sponsored by: Stormshield
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D58281
Reviewed by: glebius, pouria, markj
MFC after: 2 weeks

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