Prepare for better device categorization by moving everything to testing
subdir first.
[skip-ci]: chicken-egg problem: passing pmaports CI depends on pmbootstrap MR
depends on this MR
Related: postmarketos#16
This device is x86_64 and has a 32-bit UEFI, so I need to install
32-bit grub (AFAIK it's the only bootloader capable of loading a 64-bit
kernel from 32-bit).
The grub-efi-x86 package has been generated with pmbootstrap.