Create Initial README

Signed-off-by: Maxime Ripard <mripard@kernel.org>

README.md

+# DRM-Misc Kernel Repository 
+
+This kernel tree handles all drivers but the "big" (amd, nvidia, intel) ones,
+with a few exceptions, and most of the common infrastructure work.
+
+This branch is there to hold our templates and Gitlab configuration, chances
+are you want to look at either the
+[drm-misc-next](https://gitlab.freedesktop.org/drm/misc/kernel/-/tree/drm-misc-next)
+or
+[drm-misc-fixes](https://gitlab.freedesktop.org/drm/misc/kernel/-/tree/drm-misc-fixes)
+branches.