drm/radeon: remove UMS support

It's been deprecated behind a kconfig option for almost
two years and hasn't really been supported for years before
that.  DDX support was dropped more than three years ago.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
14 files changed