ARM: imx: Add version variable to DHSOM

Enable insertion of version variable into U-Boot environment on DHSOM,
to make it possible to check U-Boot version e.g. in U-Boot scripts.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/configs/dh_imx6_defconfig b/configs/dh_imx6_defconfig
index 007438b..3763532 100644
--- a/configs/dh_imx6_defconfig
+++ b/configs/dh_imx6_defconfig
@@ -66,6 +66,7 @@
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_USE_ETHPRIME=y
 CONFIG_ETHPRIME="FEC"
+CONFIG_VERSION_VARIABLE=y
 CONFIG_ARP_TIMEOUT=200
 CONFIG_BOUNCE_BUFFER=y
 CONFIG_DWC_AHSATA=y