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/x600_defconfig b/configs/x600_defconfig
index 4af1a21..c8f5f66 100644
--- a/configs/x600_defconfig
+++ b/configs/x600_defconfig
@@ -35,6 +35,7 @@
 CONFIG_CMD_DATE=y
 CONFIG_CMD_FAT=y
 CONFIG_CMD_FS_GENERIC=y
+CONFIG_CMD_MTDPARTS=y
 CONFIG_MTDIDS_DEFAULT="nand0=nand"
 CONFIG_MTDPARTS_DEFAULT="mtdparts=nand:64M(ubi0),64M(ubi1)"
 CONFIG_CMD_UBI=y