sandbox: Enable CMD_GETTIME

Enable this option by default on sandbox to increase build coverage.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/Kconfig b/arch/Kconfig
index 84da4e7..8af60da 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -69,6 +69,7 @@
 	select DM_SPI
 	select DM_GPIO
 	select DM_MMC
+	imply CMD_GETTIME
 	imply CMD_HASH
 	imply CMD_IO
 	imply CMD_IOTRACE