cifs_get_root(): use lookup_one_len_unlocked()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index c48ca13..09b1db2 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -642,9 +642,7 @@
 		while (*s && *s != sep)
 			s++;
 
-		inode_lock(dir);
-		child = lookup_one_len(p, dentry, s - p);
-		inode_unlock(dir);
+		child = lookup_one_len_unlocked(p, dentry, s - p);
 		dput(dentry);
 		dentry = child;
 	} while (!IS_ERR(dentry));