drm/radeon: add VCE 1.0 support v4

Initial support for VCE 1.0 using newest firmware.

v2: rebased
v3: fix for TN
v4: fix FW size calculation

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