ARM: shmobile: defconfig: Enable RZ/A1H RTC support

Enable support for the RZ/A1H Realtime Clock, which is used on the
Genmai and RSK+RZA1 boards.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200624131931.3686-8-geert+renesas@glider.be

arch/arm/configs/shmobile_defconfig

@@ -170,6 +170,7 @@ CONFIG_RTC_DRV_BQ32K=y
 CONFIG_RTC_DRV_S35390A=y
 CONFIG_RTC_DRV_RX8581=y
 CONFIG_RTC_DRV_DA9063=y
+CONFIG_RTC_DRV_SH=y
 CONFIG_DMADEVICES=y
 CONFIG_RCAR_DMAC=y
 CONFIG_RENESAS_USB_DMAC=y