drm/amdgpu/discovery: add UVD/VCN IP instance info for soc15 parts

Add secondary instance version info for vega20, arcturure, and
aldebaran.

Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>