drm/amdgpu: add register base init for aldebaran (v2)

v1: add aldebaran_reg_base_init function to initialize
register base for aldebaran (Le)
v2: update VCN HWIP and initialize base offset (James)

Signed-off-by: Le Ma <le.ma@amd.com>
Signed-off-by: James Zhu <James.Zhu@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Leo Liu <leo.liu@amd.com>
Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>