greybus: loopback: exit kfree after mutex release

init doesn't have a lock for kzalloc so exit shouldn't have lock with the
corresponding kfree.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/loopback.c

@@ -955,8 +955,8 @@ static void gb_loopback_connection_exit(struct gb_connection *connection)
 	sysfs_remove_groups(&connection->dev.kobj, loopback_con_groups);
 	debugfs_remove(gb->file);
 	list_del(&gb->entry);
-	kfree(gb);
 	mutex_unlock(&gb_dev.mutex);
+	kfree(gb);
 }
 
 static struct gb_protocol loopback_protocol = {