Felipe Lalanne c04955354a Use write + sync when writing configs to /mnt/boot
This commit updates all backends that write to /mnt/boot to do it
through a new `lib/host-utils` module. Writes are now done using write +
sync as rename is not an atomic operation in vfat.

The change also applies for writes through the `/v1/host-config`
endpoint.

Finally this change includes some improvements on tests.

Change-type: patch
2022-05-03 11:23:00 -04:00
..