habanalabs: fix DRAM usage accounting on context tear down

The patch fix the DRAM usage accounting by adding a missing update of
the DRAM memory consumption, when a context is being torn down without an
organized release of the allocated memory.
Signed-off-by: NTomer Tayar <ttayar@habana.ai>
Reviewed-by: NOded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: NOded Gabbay <oded.gabbay@gmail.com>

drivers/misc/habanalabs/memory.c

@@ -1629,6 +1629,8 @@ void hl_vm_ctx_fini(struct hl_ctx *ctx)
 			dev_dbg(hdev->dev,
 				"page list 0x%p of asid %d is still alive\n",
 				phys_pg_list, ctx->asid);
+			atomic64_sub(phys_pg_list->total_size,
+					&hdev->dram_used_mem);
 			free_phys_pg_pack(hdev, phys_pg_list);
 			idr_remove(&vm->phys_pg_pack_handles, i);
 		}