remove _datalad_buildsupport usage

setup.py

@@ -5,26 +5,20 @@
 
 import versioneer
 
-from _datalad_buildsupport.setup import BuildManPage
-
 
 # Give setuptools a hint to complain if it's too old a version
 # 30.3.0 allows us to put most metadata in setup.cfg
 # Should match pyproject.toml
 SETUP_REQUIRES = ['setuptools >= 30.3.0']
+
 # This enables setuptools to install wheel on-the-fly
 SETUP_REQUIRES += ['wheel'] if 'bdist_wheel' in sys.argv else []
 
 
-cmdclass = {
-    'build_manpage': BuildManPage
-}
-
-
 setup(
     name="datalad_metalad",
     version=versioneer.get_version(),
-    cmdclass=cmdclass,
+    cmdclass=versioneer.get_cmdclass(),
     setup_requires=SETUP_REQUIRES,
     packages=[
         'datalad_metalad',
@@ -44,8 +38,7 @@
         'datalad_metalad.pathutils',
         'datalad_metalad.pathutils.tests',
         'datalad_metalad.tests',
-        'datalad_metalad.metadatatypes',
-        '_datalad_buildsupport'
+        'datalad_metalad.metadatatypes'
     ],
     package_dir={
         'datalad_metalad.pipeline': 'datalad_metalad/pipeline'