[patch] fix compile error in serial.c

[Paul Larson]

I havn't seen a patch for this yet, so here it is.  Sorry for the duplicate 
if someone's already done it and I just didn't see it yet.

Thanks,
Paul Larson

--- linux-2.5.2-pre7/drivers/char/serial.c	Fri Jan  4 09:13:22 2002
+++ linux-new/drivers/char/serial.c	Fri Jan  4 10:01:03 2002
@@ -5827,7 +5827,7 @@
 
 static kdev_t serial_console_device(struct console *c)
 {
-	return MKDEV(TTY_MAJOR, 64 + c->index);
+	return mk_kdev(TTY_MAJOR, 64 + c->index);
 }
 
 /*