drm/amdgpu: add asic need_full_reset callback

Allow us to determine at the soc level whether the
asic requires full reset or if soft reset will work.

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>