Revert "Do no use python_provide conditionally"
    
    The macro python_provide is defined in /usr/lib/rpm/macros.d/macros.python
    in the package python-rpm-macros. But this package is not part
    of build root and therefore rpm cannot parse spec file.
    
    This reverts commit 22c180263aad50325d9e6c8a946fc8b6386fc694.
    
    (cherry picked from commit 8dd054482d1a06ccb0125740b70b483e5e0fcf5e)