Respect -q of setup.py (#14972)

Respect -q of setup.py (#14972)

Summary:
1. Changes the prints along the 'rebuild' pathway to respect the '-q' flag of setup.py
A clean rebuild now only prints:

    [zdevito@devgpu172.prn2 /data/users/zdevito/pytorch] python setup.py -q rebuild develop
    [0/1] Install the project...
    -- Install configuration: "RelWithDebInfo"
    ninja: no work to do.
    ninja: no work to do.
    ninja: no work to do.
    ninja: no work to do.
    ninja: no work to do.
    ninja: no work to do.

2. Deletes apparently dead calls to `generate_code`. Now that CMake builds these files,
it appears that it is getting called twice and the second version is never used.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/14972

Reviewed By: soumith

Differential Revision: D13396330

Pulled By: zdevito

fbshipit-source-id: 83c45143bbc6a6d2c1cfee929291ec059f2b5dc3