rename CONFIG_CMD_ENV to CONFIG_CMD_SAVEENV

The CONFIG_CMD_ENV option controls enablement of the `saveenv` command
rather than a generic "env" command, or anything else related to the
environment.  So, let's make sure the define is named accordingly.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/configs/ERIC.h b/include/configs/ERIC.h
index 1b766a7..201e62a 100644
--- a/include/configs/ERIC.h
+++ b/include/configs/ERIC.h
@@ -114,7 +114,7 @@
 
 #define CONFIG_CMD_PCI
 #define CONFIG_CMD_IRQ
-#define CONFIG_CMD_ENV
+#define CONFIG_CMD_SAVEENV
 #define CONFIG_CMD_FLASH