usb: early: xhci-dbc: use console_is_registered()

It is not reliable to check for CON_ENABLED in order to identify if a
console is registered. Use console_is_registered() instead.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-31-john.ogness@linutronix.de

drivers/usb/early/xhci-dbc.c

@@ -927,7 +927,7 @@ void __init early_xdbc_register_console(void)
 
 static void xdbc_unregister_console(void)
 {
-	if (early_xdbc_console.flags & CON_ENABLED)
+	if (console_is_registered(&early_xdbc_console))
 		unregister_console(&early_xdbc_console);
 }