u-boot-fw-utils: add hikirk config

Add machine hikirk specific u-boot environment configuration.
Configuration is done via file /etc/fw_env.config.

Signed-off-by: Mario Schuknecht <schuknecht@dresearch-fe.de>
hydraip-image.inc: add u-boot-fw-utils

Add u-boot-fw-utils to hydraip-image.inc.

Signed-off-by: Mario Schuknecht <schuknecht@dresearch-fe.de>