dm: rtc: sandbox: Enable real-time clock support

Enable real-time-clock support in sandbox.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index 5de7fbe..759f53a 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -26,3 +26,4 @@
 CONFIG_SOUND=y
 CONFIG_CMD_SOUND=y
 CONFIG_SOUND_SANDBOX=y
+CONFIG_DM_RTC=y
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 9077bb3..3092de1 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -52,7 +52,5 @@
 obj-$(CONFIG_RTC_RV3029) += rv3029.o
 obj-$(CONFIG_RTC_RX8025) += rx8025.o
 obj-$(CONFIG_RTC_S3C24X0) += s3c24x0_rtc.o
-ifdef CONFIG_DM_RTC
 obj-$(CONFIG_SANDBOX) += sandbox_rtc.o
-endif
 obj-$(CONFIG_RTC_X1205) += x1205.o
diff --git a/include/configs/sandbox.h b/include/configs/sandbox.h
index 3bf45a2..ef0efc5 100644
--- a/include/configs/sandbox.h
+++ b/include/configs/sandbox.h
@@ -207,5 +207,6 @@
 
 #define CONFIG_CMD_LZMADEC
 #define CONFIG_CMD_USB
+#define CONFIG_CMD_DATE
 
 #endif