Two of the x25 ioctl cases have error paths that break out of the function without
unlocking the socket, leading to this warning:

================================================
[ BUG: lock held when returning to user space! ]
3.10.0-rc7+ #36 Not tainted
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trinity-child2/31407 is leaving the kernel with locks still held!
1 lock held by trinity-child2/31407:
 #0:  (sk_lock-AF_X25){+.+.+.}, at: [<ffffffffa024b6da>] x25_ioctl+0x8a/0x740 [x25]
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>