drm/radeon: allow UVD to use a second 256MB segment

This improves concurrent stream decoding.

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

diff --cc drivers/gpu/drm/radeon/radeon.h
Simple merge

diff --cc drivers/gpu/drm/radeon/radeon_object.c
Simple merge

diff --cc drivers/gpu/drm/radeon/radeon_uvd.c
Simple merge