devpts: propagate error code from devpts_pty_new

Have ptmx_open() propagate any error code returned by devpts_pty_new()
(which returns either 0 or -ENOMEM anyway).

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/tty_io.c

@@ -2838,8 +2838,8 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 	filp->private_data = tty;
 	file_move(filp, &tty->tty_files);
 
-	retval = -ENOMEM;
-	if (devpts_pty_new(tty->link))
+	retval = devpts_pty_new(tty->link);
+	if (retval)
 		goto out1;
 
 	check_tty_count(tty, "ptmx_open");