MIPS: ath79: use dynamically allocated watchdog device

Remove the static watchdog device variable and use
the 'platform_device_register_simple' helper to
allocate and register the device in one step.

This allows us to save a few bytes in the kernel image.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

arch/mips/ath79/dev-common.c

@@ -101,12 +101,7 @@ void __init ath79_register_uart(void)
 	}
 }
 
-static struct platform_device ath79_wdt_device = {
-	.name		= "ath79-wdt",
-	.id		= -1,
-};
-
 void __init ath79_register_wdt(void)
 {
-	platform_device_register(&ath79_wdt_device);
+	platform_device_register_simple("ath79-wdt", -1, NULL, 0);
 }