We no longer build with pbuilder/cowbuilder, so this change removes
that unnecessary code. This also changes the `deb.sh` script which no
longer needs parameters since it's only purpose is now to build the
source package, and removes the no-longer needed targets from `Makefile`.
This solves #9356 as good as possible. We still have the list of
distributions in two places, but I don't see a way to import the list
of distributions to the packaging GHA.
Fixes: #9356
For auto-generating help files we need `buildtools`, so we can't
exclude it from source package. Also, we now include our version
of `help2man`, so we no longer need it as a build dependency,
but instead directly depend on `perl`.
more things needed in some README.repo
cow.sh: make it compatible with xenial
set DIST for use with optional local .pbuilderrc, also in deb.sh
link linux/.pbuilderrc to ~/.pbuilderrc if it doesn't exist
