configs: agilex5_defconfig: Rename mtd partition to root

This patch is to rename mtd partition to root to align with
agilex.

Signed-off-by: Dinesh Maniyam <[email protected]>

Author: dineshmaniyam

configs/socfpga_agilex5_defconfig

@@ -63,7 +63,7 @@ CONFIG_SPL_SPI_FLASH_MTD=y
 CONFIG_SPI_FLASH_MTD=y
 CONFIG_SPL_MTD_SUPPORT=y
 CONFIG_MTDIDS_DEFAULT="nand0=10b80000.nand.0"
-CONFIG_MTDPARTS_DEFAULT="mtdparts=10b80000.nand.0:2m(u-boot),-(rootubi)"
+CONFIG_MTDPARTS_DEFAULT="mtdparts=10b80000.nand.0:2m(u-boot),-(root)"
 CONFIG_CMD_UBI=y
 CONFIG_CMD_UBIFS=y
 CONFIG_MTD_UBI=y