Use ninja to generate dep files for the native build
This introduce a python script that is able to generate dep files from ninja.
The script is used to generate a proper dep file for re-running cmake for the native build, but it is generic and can be used for the native targets in the future.
Depends on D5624
ninja ninja # Check native build isn't ran again. touch build.ninja ninja # Native build runs again.
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Differential Revision: https://reviews.bitcoinabc.org/D5628