AFAICT this is super mundane. Devs added some checks that when run will drop .hdrtest files all over the source tree when you do a normal build. This is really unclean and has practical ramifications even if you gitignore them as Linus points out. Pretty much any lead developer would be upset if someone tried to merge something like this in a software project, and it has essentially nothing to do with the particular drivers or code functionality.