watchdog: Fix dependencies for !HAS_IOMEM archs

Not every arch has io memory.
So, unbreak the build by fixing the dependencies.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/Kconfig

@@ -146,6 +146,7 @@ config TANGOX_WATCHDOG
 	tristate "Sigma Designs SMP86xx/SMP87xx watchdog"
 	select WATCHDOG_CORE
 	depends on ARCH_TANGO || COMPILE_TEST
+	depends on HAS_IOMEM
 	help
 	  Support for the watchdog in Sigma Designs SMP86xx (tango3)
 	  and SMP87xx (tango4) family chips.
@@ -618,6 +619,7 @@ config DIGICOLOR_WATCHDOG
 config LPC18XX_WATCHDOG
 	tristate "LPC18xx/43xx Watchdog"
 	depends on ARCH_LPC18XX || COMPILE_TEST
+	depends on HAS_IOMEM
 	select WATCHDOG_CORE
 	help
 	  Say Y here if to include support for the watchdog timer
@@ -1374,6 +1376,7 @@ config BCM_KONA_WDT_DEBUG
 config BCM7038_WDT
 	tristate "BCM7038 Watchdog"
 	select WATCHDOG_CORE
+	depends on HAS_IOMEM
 	help
 	 Watchdog driver for the built-in hardware in Broadcom 7038 SoCs.