drm/amdkfd: Cleanup qpd.pqm initialization

The PQM doesn't change after process creation. So initialize it in
kfd_create_process_device_data.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>