Bug#972330: pcp build-depends on python3-all-dev, but only builds for the default python3 version

[Matthias Klose]

Package: src:pcp
Version: 5.2.1-1

pcp buid-depends on:

  python3-all-dev, python3-dev

but only builds for the default python3 version.

So either build for all supported python3 versions and drop the python3-dev b-d,
or drop the python3-all-dev b-d.