python: Improve Python detection.
* m4/python.m4 (_AM_PYTHON_INTERPRETER_LIST): Prefer the generic 'pythonX' over 'pythonX.Y'. This way we select the users preferred version for both flavors. Prefer 'python' over 'python3' but not over 'python2' so that the algorithm still finds a 'python2' even if 'python' is a Python3.
- Fixes-commit: 5189c08af9468cdeb6f16a6ecd0fee53e1e3aa0e
- Signed-off-by: Justus Winter <justus@g10code.com>