Blender Git Loki

install_deps: Enable PIC in Python static library.

Update for D3078, I think it should be fixed

Benefits:
- after installing python 3.7 with `./build_files/build_environment/install_deps.sh`, user will be able to run `make bpy` without linking error:
- https://blender.stackexchange.com/questions/102933/a-working-guidance-for-building-blender-as-bpy-python-module
- https://stackoverflow.com/questions/36779834/compiling-blender-bpy-recompile-with-fpic

To prevent errors like `/opt/lib/python-3.7.4/bin/python3.7: error while loading shared libraries: libpython3.7m.so.1.0: cannot open shared object file: No such file or directory`, add python .so lib to ldconfig

Reviewed By: mont29

Differential Revision: https://developer.blender.org/D7177