defconfigs: Migrate CONFIG_SYS_REDUNDAND_ENVIRONMENT

Move this symbol to Kconfig.  As part of this we can drop a UBI-specific
symbol that was a stop-gap for not having this particular symbol in
Kconfig.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/kmcoge4_defconfig b/configs/kmcoge4_defconfig
index 7ee4ce4..3b7ee33 100644
--- a/configs/kmcoge4_defconfig
+++ b/configs/kmcoge4_defconfig
@@ -36,6 +36,7 @@
 # CONFIG_CMD_UBIFS is not set
 CONFIG_DOS_PARTITION=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
+CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
 CONFIG_BOOTCOUNT_LIMIT=y
 CONFIG_BOOTCOUNT_BOOTLIMIT=3
 # CONFIG_MMC is not set