Revert "Revert "drm/amdkfd: Add heavy-weight TLB flush after unmapping""

This reverts commit 430f8e6edbaac8abfddf76f1aef732d9c6257211.

Revert reason: Issue has been resolved.

Signed-off-by: Eric Huang <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdkfd/kfd_chardev.c

···
 			       i, args->n_devices);
 			goto unmap_memory_from_gpu_failed;
 		}
+		kfd_flush_tlb(peer_pdd, TLB_FLUSH_HEAVYWEIGHT);
 		args->n_success = i+1;
 	}
 	kfree(devices_arr);