drm/amdkfd: Dequeue user queues when process mm released

drm/amdkfd: Dequeue user queues when process mm released

Move dequeue user queues and destroy user queues from
kfd_process_wq_release to mmu notifier release callback, to ensure no
system memory access from GPU because the process memory is going to
free from CPU after mmu release notifier callback returns.

Destroy queue releases the svm prange queue_refcount, this also removes
fake flase positive warning message "Freeing queue vital buffer" message
if application crash or killed.

Suggested-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>