waf.py: SyntaxWarning: invalid escape sequence

Summary

I am adapting our CI pipeline which build the RTEMS Docs to the latest changes and recognized the following warnings:

$ cd rtems-docs
$ ./waf configure --plantuml --ditaa --pdf --singlehtml --prefix=/home/minna/src/artifacts/html

/home/minna/src/rtems-docs/common/waf.py:111: SyntaxWarning: invalid escape sequence '\D'
  ver = tuple(map(int, re.split('[\D]', version)))

/home/minna/src/rtems-docs/common/waf.py:118: SyntaxWarning: invalid escape sequence '\D'
  ver = tuple(map(int, re.split('[\D]', version)))

/home/minna/src/rtems-docs/common/latex.py:9: SyntaxWarning: invalid escape sequence '\d'
  '\documentclass[a4paper,11pt,english]{report}']

Moreover, using OpenSUSE as basis for the builds, the python package distro is missing:

$ ./waf configure --plantuml --ditaa --pdf --singlehtml --prefix=/home/minna/src/artifacts/html
[...]
Checking for program 'pdf2ps'                  : /usr/bin/pdf2ps 
Checking for program 'makeglossaries'          : /usr/bin/makeglossaries 
Traceback (most recent call last):
  File "/home/minna/src/rtems-docs/common/latex.py", line 85, in host_name
    from distro import linux_distribution
ModuleNotFoundError: No module named 'distro'

This missing module can easily installed in the environment with pip install distro.

Steps to reproduce

See README.md

Pre-set options