net/mlx5: SF: Fix memory leak of work item

Cited patch in the fixes tag missed to free the allocated work.
Fix it by freeing the work after work execution.

Fixes: f3196bb0 ("net/mlx5: Introduce vhca state event notifier")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/sf/vhca_event.c

@@ -94,6 +94,7 @@ static void mlx5_vhca_state_work_handler(struct work_struct *_work)
 	struct mlx5_core_dev *dev = notifier->dev;
 
 	mlx5_vhca_event_notify(dev, &work->event);
+	kfree(work);
 }
 
 static int