ubi: env: fix redundand management

We check (with a #if defined()) the config ENV_UBI_VOLUME_REDUND
to know if there is a redundant env. But this config is a string
and is always defined with env is in ubi, so we always consider
that a redundand env is used.

To fix this issue, I've added a hidden flag ENV_UBI_IS_VOLUME_REDUND
that is true when ENV_UBI_VOLUME_REDUND is not "". Then, I check
this flag in the code, instead of the string ENV_UBI_VOLUME_REDUND.

hs: fixed typo s/condider/consider
Signed-off-by: NPhilippe Reynes <philippe.reynes@softathome.com>
Reviewed-by: NHeiko Schocher <hs@denx.de>

env/Kconfig

@@ -516,6 +516,12 @@ config ENV_UBI_VOLUME_REDUND
 	help
 	  Name of the redundant volume that you want to store the environment in.
 
+config ENV_UBI_IS_VOLUME_REDUND
+	bool
+	depends on ENV_IS_IN_UBI
+	default y if ENV_UBI_VOLUME_REDUND != ""
+	default n
+
 config ENV_UBI_VID_OFFSET
 	int "ubi environment VID offset"
 	depends on ENV_IS_IN_UBI

include/env_internal.h

@@ -101,7 +101,7 @@ extern unsigned long nand_env_oob_offset;
 # ifndef CONFIG_ENV_UBI_VOLUME
 #  error "Need to define CONFIG_ENV_UBI_VOLUME when using CONFIG_ENV_IS_IN_UBI"
 # endif
-# if defined(CONFIG_ENV_UBI_VOLUME_REDUND)
+# if defined(CONFIG_ENV_UBI_IS_VOLUME_REDUND)
 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
 # endif
 # ifndef CONFIG_ENV_SIZE