When the timeout occurs it is important to ensure clean up of child
processes. Killing only the direct process created by a command can
leave child processes running.

For example a pmbootstrap.py install will run apk add. This run command
creates multiple processes as follows:
(cmd line arguments snipped for readability)

  $ ps -e -o pid,ppid,pgid,cmd
  PID  PPID  PGID CMD
  31738 23247 31738 python3 ./pmbootstrap.py -t 15 install --no-fde
  31746 31738 31738 sudo env -i /bin/sh -c ... ;apk --no-progress add
  31747 31746 31738 /bin/sh -c ... ;apk --no-progress add
  31748 31747 31738 apk --no-progress add

The root process of the run command is PID 31746. We want to kill
the child processes too. Otherwise only running kill -9 31746 will leave
the processes 31747 and 31748 running.

(imagine epic music playing in background)

Max Justicz found a clever way to exploit apk, which is fixed in the
latest version:

<https://justi.cz/security/2018/09/13/alpine-apk-rce.html>

so:libprotobuf.so.15 does not exist anymore in Alpine edge

When cross compiling, the kernel scripts would be in the native arch
again. That was already fixed in !1234, however the mime type of the
binaries has changed, so we couldn't detect them properly anymore
(#1659).

This commit fixes it again, and also adds a checks so this won't
silently fail in the future.

[skip ci] because this would not run through anyway (building these
packages takes too long). Fixes #1659.

Update happened upstream in Alpine edge:
https://github.com/alpinelinux/aports/pull/4983

The pmbootstrap alias cannot be used within the script.
The reason is that aliases are not expanded in non-interactive shells.
reference: https://unix.stackexchange.com/q/1496

To fix this replace references to the pmbootstrap alias with
the $pmbootstrap variable

[skip ci]

recovery zip: support twrp.fstab filename in addition to recovery.fstab (fix for compatibility with TWRP on sony-yuga)

Fixes #1625.

Rebuild libphonenumber, because a soname it depends upon does not exist
anymore: so:libboost_system-mt.so.1.66.0

There are devices where charging-sdl/directfb fails (osk-sdl#77).

It's nicer to give an error message than display "Loading..." forever.