The `msm-fb-refresher` updates the screen for msm based devices. It is
not needed for all devices, so we had some extra code in the initramfs,
that would only add it when the `deviceinfo_msm_refresher` variable was
set. However, we are able now to add files to initramfs hooks, so this
hack can be removed and simplify everything.
Changes:
* Remove `deviceinfo_msm_refresher` from all deviceinfos
* Add sanity check for it
* Move all `deviceinfo` sanity checks to an extra function
* `postmarketos-mkinitfs`: remove code for msm refresher
* `msm-fb-refresher`: add initramfs hook
* Add nonfree_firmware subpackage to all devices, that depend on
nonfree firmware.
* Some packages were depending on `linux-firmware`, but without having
Wifi working. Removed that dependency as it was probably added by
accident. If it was really necessary, chosing the appropriate
split linux-firmware package (e.g. linux-firmware-brcm) is better
anyway (that has been changed recently in Alpine and is possible
now).
* Add a test case that makes sure we don't have firmware depends
without subpackages in device aports anymore.
