drm/amdgpu: fix for suspend/resume kiq fence fallback under sriov

- in device_resume, sriov configure interrupt should be in full access,
  so release_full_gpu should be done after kfd_resume.
- remove the previous workaround solution for sriov.

Fixes: ec4927d4

 ("drm/amdgpu: fix for suspend/resume sequence under sriov")
Signed-off-by: Shikang Fan <shikang.fan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>