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/kmcoge5ne_defconfig b/configs/kmcoge5ne_defconfig
index faeb0c7..edd9af9 100644
--- a/configs/kmcoge5ne_defconfig
+++ b/configs/kmcoge5ne_defconfig
@@ -177,6 +177,7 @@
 CONFIG_MTDPARTS_DEFAULT="mtdparts=boot:768k(u-boot),128k(env),128k(envred),-(ubi0);app:-(ubi1);"
 CONFIG_CMD_UBI=y
 # CONFIG_CMD_UBIFS is not set
+CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
 CONFIG_BOOTCOUNT_LIMIT=y
 CONFIG_BOOTCOUNT_BOOTLIMIT=3
 # CONFIG_MMC is not set