rtc: mxc{,_v2}: enable COMPILE_TEST

Extend code coverage for the rtc-mxc and rtc-mxc-v2 drivers.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20201121224529.568237-1-alexandre.belloni@bootlin.com

drivers/rtc/Kconfig

@@ -1756,7 +1756,9 @@ config RTC_DRV_LOONGSON1
 
 config RTC_DRV_MXC
 	tristate "Freescale MXC Real Time Clock"
-	depends on ARCH_MXC
+	depends on ARCH_MXC || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
 	help
 	   If you say yes here you get support for the Freescale MXC
 	   RTC module.
@@ -1766,7 +1768,9 @@ config RTC_DRV_MXC
 
 config RTC_DRV_MXC_V2
 	tristate "Freescale MXC Real Time Clock for i.MX53"
-	depends on ARCH_MXC
+	depends on ARCH_MXC || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
 	help
 	   If you say yes here you get support for the Freescale MXC
 	   SRTC module in i.MX53 processor.