console: Preserve index after console setup()

Before register_console() calls the setup() method of the matched
console, the registering console index is already equal to the index
from the console command line; ie. newcon->index == c->index.

This change is also required to support extensible console matching;
(the command line index may have no relation to the console index
assigned by the console-defined match() function).
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/printk/printk.c

@@ -2479,7 +2479,6 @@ void register_console(struct console *newcon)
 		    newcon->setup(newcon, console_cmdline[i].options) != 0)
 			break;
 		newcon->flags |= CON_ENABLED;
-		newcon->index = c->index;
 		if (i == selected_console) {
 			newcon->flags |= CON_CONSDEV;
 			preferred_console = selected_console;