Full refactor and add q6voiced

This is a major overhaul of the entire package:

• manage bootmac as a subproject as this part has its own upstream repo
• move all files from the root to appropriate subfolders
• add meson.build to automatically build & install subprojects
• import q6voiced as a Meson subproject as well and create wrapper script

As this is a native package with no single upstream, patches for bootmac and q6voiced are managed using the corresponding Meson subproject features rather than d/patches, as the later would complicate things when using git-buildpackage (require upstream tag, pristine-tar branch...).

Finally, as q6voiced is a compiled executable, the package now needs to be arch-any instead of the arch-all used so far.