This commit add u-boot env config for GL-MT3000, so
that we can use fw_printenv to print u-boot env and
use fw_setenv to set u-boot env in GL-MT3000.
Signed-off-by: Jianhui Zhao <zhaojh329@gmail.com>
(cherry picked from commit 6892603efa11603c6f365bee1cf94e98336d72aa)
42c99789ac