drm changes and updating to 12.0

[Robert Huff]

	I have a set of older machines (e.g. AMD Phenom II, Radeon HD3300
gpu) which will be updated from 11.<smallnum> to 12.0 once 12 is out
and the initial round of bugs are squashed.
	One system is being done now, to allow time to catch any major
problems and then plan the update process.
	Looking at src/UPDATING, the only thing I don't understand is the
whole drm-kmod change.  Is there an authoritative write-up on what's
going on, how to choose the right drivers for my hardware, and how to
do this from source without forcing a fresh install?


				Respectrfully,


					Robert Huff