[PATCH] bonding: fix a locking bug in bond_release

bond_release returns EINVAL without releasing the bond lock if the
slave device is not being bonded by the bond.  The following patch
ensures that the lock is released in this case.

Signed-off-by: Stephen J. Bevan <stephen@dino.dnsalias.com>
Acked-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>