Summary:
The new class is responsible for parsing EDID blobs. It has pretty
straightforward API: you hand blob data to the constructor and after
that you're ready to query parsed data, e.g. physical size, etc.
The main reason to extract EDID parsing code into a class is to clean up
drm_output.cpp a bit.
Test Plan: Compiles, the DRM platform still works.
Reviewers: #kwin, davidedmundson
Reviewed By: #kwin, davidedmundson
Subscribers: davidedmundson, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D22211
