rtc: snvs: select option REGMAP_MMIO

Select REGMAP_MMIO to fix the following build error seen with x86_64
randconfig.

  drivers/built-in.o: In function `snvs_rtc_probe':
rtc-snvs.c:(.text+0x567730): undefined reference to `devm_regmap_init_mmio_clk'

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Acked-by: Frank Li <Frank.Li@freescale.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 83b4b89b9d5a..533bfa3b6039 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1523,6 +1523,7 @@ config RTC_DRV_MXC
 
 config RTC_DRV_SNVS
         tristate "Freescale SNVS RTC support"
+        select REGMAP_MMIO
         depends on HAS_IOMEM
         depends on OF
         help