rtc: fix build error

Fix the following build errors reported by kbuild test robot by selecting
REGMAP_SPI in Kconfig file

drivers/built-in.o: In function `ds1343_probe':
rtc-ds1343.c:(.text+0x1baf8f): undefined reference to `devm_regmap_init_spi'
Signed-off-by: NRaghavendra Chandra Ganiga <ravi23ganiga@gmail.com>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/Kconfig

@@ -574,6 +574,7 @@ config RTC_DRV_DS1305
 	  will be called rtc-ds1305.
 
 config RTC_DRV_DS1343
+	select REGMAP_SPI
 	tristate "Dallas/Maxim DS1343/DS1344"
 	help
 	  If you say yes here you get support for the