Build (or provide instructions to build) everything from source

[UniversalSuperBox]

Halium developers have expressed concern that ubports-boot is shipped as binary blobs which are built into the initramfs. This is desirable so the initrd will be predictable between build configurations, however it makes sense to allow builds from source as well. Either change the configuration of ubports-boot so that it builds its binaries from source, or provide instructions so that other developers can do this.

[crutchcorn]

This is important for maintaining transparency as well as allowing contributors and to-be maintiainers to jump in and help where needed.