drivers/ams: Set default values in Kconfig

Set default values for the hex and int kconfig symbols so they don't
come up as undefined.

Change-Id: If104cbf7d84719a63fb80aa955efa8baa3953d09
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: http://review.coreboot.org/12498
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/drivers/ams/Kconfig

@@ -6,7 +6,9 @@ config DRIVERS_AS3722_RTC
 config DRIVERS_AS3722_RTC_BUS
 	int "AS3722 RTC bus"
 	depends on DRIVERS_AS3722_RTC
+	default 0
 
 config DRIVERS_AS3722_RTC_ADDR
 	hex "AS3722 RTC chip address"
 	depends on DRIVERS_AS3722_RTC
+	default 0x00