net: Split a __sys_listen helper for io_uring

net: Split a __sys_listen helper for io_uring

io_uring holds a reference to the file and maintains a sockaddr_storage
address.  Similarly to what was done to __sys_connect_file, split an
internal helper for __sys_listen in preparation to support an
io_uring listen command.

Reviewed-by: Jens Axboe <[email protected]>
Signed-off-by: Gabriel Krisman Bertazi <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Acked-by: Jakub Kicinski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>