get rid of bundled init_cinderx

Summary: Instead of this, we'll just inject it into our builds similar to how we inject a dependency on `//cinderx:_cinderx`

Reviewed By: itamaro, alexmalyshev

Differential Revision: D70263853

fbshipit-source-id: fe566e19e32ca3219b2723bf82ec70d5fe3689a2

Author: Aniket Panse