configs: Migrate and re-enabled CONFIG_CMD_MTDPARTS

Now that CMD_UBI does not select CMD_MTDPARTS we need to make platforms
that had been enabling it turn it on by hand.  This exposed that we had
not yet migrated CMD_MTDPARTS fully, so do so now.

Fixes: 86dfa556d927 ("cmd: ubi: Remove useless call to mtdparts_init()")
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/mgcoge3un_defconfig b/configs/mgcoge3un_defconfig
index e834a14..0c2785c 100644
--- a/configs/mgcoge3un_defconfig
+++ b/configs/mgcoge3un_defconfig
@@ -22,6 +22,7 @@
 CONFIG_CMD_MII=y
 CONFIG_CMD_PING=y
 CONFIG_CMD_JFFS2=y
+CONFIG_CMD_MTDPARTS=y
 CONFIG_MTDIDS_DEFAULT="nand0=orion_nand"
 CONFIG_MTDPARTS_DEFAULT="mtdparts=orion_nand:-(ubi0);"
 CONFIG_CMD_UBI=y