openharmony-standard: restart systemd services on failures

Adding `Restart=on-failure` to all openharmony services

weston service is hanging at startup (SIGHUP) on raspberrypi4-64
adding `Restart=always` to systemd unit to restart
weston service when hanging. `Restart=on-failure` is not enough here.

Signed-off-by: Francesco Pham <francesco.pham@huawei.com>