rtc: xgene: Set hardware dependency

The rtc-xgene driver is only useful on X-Gene SoC.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Iyappan Subramanian <isubramanian@apm.com>
Cc: Keyur Chudgar <kchudgar@apm.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

drivers/rtc/Kconfig

@@ -1533,6 +1533,7 @@ config RTC_DRV_MOXART
 config RTC_DRV_XGENE
 	tristate "APM X-Gene RTC"
 	depends on HAS_IOMEM
+	depends on ARCH_XGENE || COMPILE_TEST
 	help
 	  If you say yes here you get support for the APM X-Gene SoC real time
 	  clock.