cmd: add Kconfig option for 'date' command

Signed-off-by: Chris Packham <judge.packham@gmail.com>
[trini: default y if DM_RTC, re-sync]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/glacier_defconfig b/configs/glacier_defconfig
index 5a82757..3fb53cc 100644
--- a/configs/glacier_defconfig
+++ b/configs/glacier_defconfig
@@ -19,6 +19,7 @@
 CONFIG_CMD_PING=y
 CONFIG_CMD_SNTP=y
 CONFIG_CMD_CACHE=y
+CONFIG_CMD_DATE=y
 CONFIG_MAC_PARTITION=y
 CONFIG_DOS_PARTITION=y
 CONFIG_ISO_PARTITION=y