watchdog: Fix Elan SC520 dependencies

Anyone using a system based on an AMD Elan SC520 processor would be
building a dedicated kernel for it, so we can make the sc520_wdt
driver depend on MELAN. SC520_CPUFREQ already depends on MELAN so it
makes things more consistent. It also makes kernel configuration for
every other x86 user easier.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

drivers/watchdog/Kconfig

@@ -553,7 +553,7 @@ config GEODE_WDT
 
 config SC520_WDT
 	tristate "AMD Elan SC520 processor Watchdog"
-	depends on X86
+	depends on MELAN
 	help
 	  This is the driver for the hardware watchdog built in to the
 	  AMD "Elan" SC520 microcomputer commonly used in embedded systems.