[WATCHDOG] max63xx driver depends on ioremap()

Correct fix for the "ioremap() causes build failure on S390" should have been
a dependancy on HAS_IOMEM. So we add this dependancy also (and leave the driver
in the ARM section for now).
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

drivers/watchdog/Kconfig

@@ -302,7 +302,7 @@ config TS72XX_WATCHDOG
 
 config MAX63XX_WATCHDOG
 	tristate "Max63xx watchdog"
-	depends on ARM
+	depends on ARM && HAS_IOMEM
 	help
 	  Support for memory mapped max63{69,70,71,72,73,74} watchdog timer.