drm/amdgpu: Add callback get xcp resource info

Add a callback interface to get the resource information of a partition
mode. Presently the information has number of resources and number of
entities sharing the resource.

Add the implementation for aquavanjaram SOCs.

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Asad Kamal <asad.kamal@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>