drm/amdgpu: kfd_pre_reset outside req_full_gpu cause sriov hang

XGMI hive put kfd_pre_reset into amdgpu_device_lock_adev,
but outside req_full_gpu of sriov.
It would make sriov hang during reset.

Signed-off-by: Wentao Lou <Wentao.Lou@amd.com>
Reviewed-by: Shaoyun Liu <Shaoyun.Liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>