Change the values of sysconfig's "posix_prefix" install scheme to /usr/local
    
    - when RPM build or venv/virtualenv is not detected
    - replaces the patch for distutils, as distutils is deprecated
    
    The original values are saved as an additional "rpm_prefix" install scheme.
    
    See https://discuss.python.org/t/pep-632-deprecate-distutils-module/5134/104
    for a more detailed rationale.
    
    Downstream only for now, waiting for https://bugs.python.org/issue43976