env: Rename SYS_REDUNDAND_ENVIRONMENT to ENV_REDUNDANT

Rename the variable and add ENV_ prefix, so that all configuration
options which are related to environment would have an CONFIG_ENV_
prefix. No functional change.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/env/sf.c b/env/sf.c
index eb4c8d5..0b70e18 100644
--- a/env/sf.c
+++ b/env/sf.c
@@ -380,7 +380,7 @@
 
 	tmp_env1 = (env_t *)memalign(ARCH_DMA_MINALIGN,
 			CONFIG_ENV_SIZE);
-	if (IS_ENABLED(CONFIG_SYS_REDUNDAND_ENVIRONMENT))
+	if (IS_ENABLED(CONFIG_ENV_REDUNDANT))
 		tmp_env2 = (env_t *)memalign(ARCH_DMA_MINALIGN,
 					     CONFIG_ENV_SIZE);
 
@@ -394,7 +394,7 @@
 	read1_fail = spi_flash_read(env_flash, CONFIG_ENV_OFFSET,
 				    CONFIG_ENV_SIZE, tmp_env1);
 
-	if (IS_ENABLED(CONFIG_SYS_REDUNDAND_ENVIRONMENT)) {
+	if (IS_ENABLED(CONFIG_ENV_REDUNDANT)) {
 		read2_fail = spi_flash_read(env_flash,
 					    CONFIG_ENV_OFFSET_REDUND,
 					    CONFIG_ENV_SIZE, tmp_env2);
@@ -429,7 +429,7 @@
 	spi_flash_free(env_flash);
 
 	free(tmp_env1);
-	if (IS_ENABLED(CONFIG_SYS_REDUNDAND_ENVIRONMENT))
+	if (IS_ENABLED(CONFIG_ENV_REDUNDANT))
 		free(tmp_env2);
 out:
 	/* env is not valid. always return 0 */