build: Tune M4 macros for our needs.
* m4/ax_python_devel.m4: Do not emit 'HAVE_PYTHON'. * m4/python.m4 (_AM_PYTHON_INTERPRETER_LIST): Add newer Python versions, drop older ones. Also, sort the list with older versions at the front, newer and generic versions towards the end. This makes the algorithm pick the lowest version that meets the version requirement.
- Signed-off-by: Justus Winter <justus@g10code.com>