uboot-mediatek: fixes defconfig typo for Linksys E8450

CONFIG_CMD_MTDPART does not exist, fix it.

Fixes: ed50004 ("uboot-mediatek: add support for Linksys E8450")
Signed-off-by: Chukun Pan <[email protected]>

package/boot/uboot-mediatek/patches/410-add-linksys-e8450.patch

@@ -58,7 +58,7 @@
 +CONFIG_CMD_LINK_LOCAL=y
 +# CONFIG_CMD_MBR is not set
 +CONFIG_CMD_MTD=y
-+CONFIG_CMD_MTDPART=y
++CONFIG_CMD_MTDPARTS=y
 +CONFIG_CMD_PCI=y
 +CONFIG_CMD_SF_TEST=y
 +CONFIG_CMD_PING=y