[ROSE/AX25] af_rose: rose_release() fix

rose_release() doesn't release sockets properly, e.g. it skips
sock_orphan(), so OOPSes are triggered in sock_def_write_space(),
which was observed especially while ROSE skbs were kfreed from
ax25_frames_acked(). There is also sock_hold() and lock_sock() added -
similarly to ax25_release(). Thanks to Bernard Pidoux for substantial
help in debugging this problem.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Reported-and-tested-by: Bernard Pidoux <bpidoux@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>