env: Discern environment coming from external storage

Add another custom environment flag which discerns environment coming
from external storage from environment set by U-Boot itself.

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>

env/remote.c

@@ -45,7 +45,7 @@ static int env_remote_save(void)
 static int env_remote_load(void)
 {
 #ifndef ENV_IS_EMBEDDED
-	return env_import((char *)env_ptr, 1);
+	return env_import((char *)env_ptr, 1, H_EXTERNAL);
 #endif
 
 	return 0;