__d_unalias() doesn't use inode argument

... and hasn't since 2015.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/dcache.c

@@ -3045,8 +3045,7 @@ struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2)
  * Note: If ever the locking in lock_rename() changes, then please
  * remember to update this too...
  */
-static int __d_unalias(struct inode *inode,
-		struct dentry *dentry, struct dentry *alias)
+static int __d_unalias(struct dentry *dentry, struct dentry *alias)
 {
 	struct mutex *m1 = NULL;
 	struct rw_semaphore *m2 = NULL;
@@ -3127,7 +3126,7 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
 					inode->i_sb->s_id);
 			} else if (!IS_ROOT(new)) {
 				struct dentry *old_parent = dget(new->d_parent);
-				int err = __d_unalias(inode, dentry, new);
+				int err = __d_unalias(dentry, new);
 				write_sequnlock(&rename_lock);
 				if (err) {
 					dput(new);