- add `GRUB_CMDLINE_LINUX_DEFAULT` with `efi=noruntime clk_ignore_unused pd_ignore_unused` so it actually boots
- use `grub-with-dtb` for the (required) DTB usage in grub
- use a customize hook to add a lot of modules & fw into initrd, required for booting
- if on RELEASE=lunar, add Ubuntu's "x13s Concept" PPA and a few packages for battery control/audio