One last oversight from dropping of Python 2

Author: dralley

.gitignore

@@ -7,5 +7,6 @@ doc/c/Doxyfile.in
 librepo-*.tar.xz
 librepo-*.rpm
 python-librepo-*.rpm
+python3-librepo-*.rpm
 BUG*
 ISSUE*

doc/python/CMakeLists.txt

@@ -1,5 +1,5 @@
 ADD_CUSTOM_TARGET (doc-python
-    PYTHONPATH=${CMAKE_BINARY_DIR}/librepo/python/python${PYTHON_VERSION_MAJOR} sphinx-build -E -b html
+    PYTHONPATH=${CMAKE_BINARY_DIR}/librepo/python/ sphinx-build -E -b html
                   ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR}
                   COMMENT "Building Python API documentation with Sphinx")