mlxsw: core: Fix use-after-free calling devl_unlock() in mlxsw_core_bus_device_unregister()

Do devl_unlock() before freeing the devlink in
mlxsw_core_bus_device_unregister() function.
Reported-by: Ido Schimmel <idosch@nvidia.com>
Fixes: 72a4c8c9 ("mlxsw: convert driver to use unlocked devlink API during init/fini")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20220721142424.3975704-1-jiri@resnulli.usSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -2296,8 +2296,8 @@ void mlxsw_core_bus_device_unregister(struct mlxsw_core *mlxsw_core,
 		devl_resources_unregister(devlink);
 	mlxsw_core->bus->fini(mlxsw_core->bus_priv);
 	if (!reload) {
-		devlink_free(devlink);
 		devl_unlock(devlink);
+		devlink_free(devlink);
 	}
 
 	return;
@@ -2305,8 +2305,8 @@ void mlxsw_core_bus_device_unregister(struct mlxsw_core *mlxsw_core,
 reload_fail_deinit:
 	mlxsw_core_params_unregister(mlxsw_core);
 	devl_resources_unregister(devlink);
-	devlink_free(devlink);
 	devl_unlock(devlink);
+	devlink_free(devlink);
 }
 EXPORT_SYMBOL(mlxsw_core_bus_device_unregister);