eCryptFS: fix imbalanced mutex locking

Fix imbalanced calls for mutex lock/unlock on ecryptfs_daemon_hash_mux
Revealed by Ingo Molnar: http://lkml.org/lkml/2008/5/7/260

Signed-off-by: Cyrill Gorcunov <[e-mail]>
Cc: Michael Halcrow <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/ecryptfs/miscdev.c

···
 	mutex_lock(&daemon->mux);
 	if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
 		rc = 0;
+		mutex_unlock(&ecryptfs_daemon_hash_mux);
 		printk(KERN_WARNING "%s: Attempt to read from zombified "
 		       "daemon\n", __func__);
 		goto out_unlock_daemon;
 	}
 	if (daemon->flags & ECRYPTFS_DAEMON_IN_READ) {
 		rc = 0;
+		mutex_unlock(&ecryptfs_daemon_hash_mux);
 		goto out_unlock_daemon;
 	}
 	/* This daemon will not go away so long as this flag is set */