[PATCH] ppc32: Fix booting on some OldWolrd Macs

It seems that on some OldWolrd macs, we don't get the OF stdout device,
thus the new set_preferred_console() dies at boot trying to dereference
a NULL pointer.

Trivial fix.

arch/ppc/kernel/setup.c

@@ -484,6 +484,9 @@ static int __init set_preferred_console(void)
 	char *name;
 	int offset;
 
+	if (of_stdout_device == NULL)
+		return -ENODEV;
+
 	/* The user has requested a console so this is already set up. */
 	if (strstr(saved_command_line, "console="))
 		return -EBUSY;