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/ppmc7xx.h b/include/configs/ppmc7xx.h
index 577ab8e..0fd8635 100644
--- a/include/configs/ppmc7xx.h
+++ b/include/configs/ppmc7xx.h
@@ -83,7 +83,7 @@
 #include <config_cmd_default.h>
 
 #define CONFIG_CMD_FLASH
-#define CONFIG_CMD_ENV
+#define CONFIG_CMD_SAVEENV
 #define CONFIG_CMD_RUN
 #define CONFIG_CMD_ELF
 #define CONFIG_CMD_NET