ARM: rmobile: beacon: Support RZ/G2 [M/N/H] on TARGET_BEACON_RZG2M

The three different boards share the same board file and only differ
in terms of which SoC is being used.  By enabling FIT on
TARGET_BEACON_RZG2M, it can support all three boards and elimate
duplicate code.

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/configs/r8a774a1_beacon_defconfig b/configs/r8a774a1_beacon_defconfig
index 4e52dd0..2b1057f 100644
--- a/configs/r8a774a1_beacon_defconfig
+++ b/configs/r8a774a1_beacon_defconfig
@@ -33,6 +33,9 @@
 CONFIG_CMD_FAT=y
 CONFIG_CMD_FS_GENERIC=y
 CONFIG_OF_CONTROL=y
+CONFIG_OF_LIST="r8a774a1-beacon-rzg2m-kit r8a774b1-beacon-rzg2n-kit r8a774e1-beacon-rzg2h-kit"
+CONFIG_MULTI_DTB_FIT_LZO=y
+CONFIG_MULTI_DTB_FIT_USER_DEFINED_AREA=y
 CONFIG_ENV_OVERWRITE=y
 CONFIG_ENV_IS_IN_MMC=y
 CONFIG_SYS_MMC_ENV_DEV=1