legacy confile: fix legacy network parser

legacy confile: fix legacy network parser

This fixes a bug introduced by:

commit 94f0035bf636ba853451d59c129e26d94850c04d
Author: Christian Brauner <christian.brauner@ubuntu.com>
Date:   Thu Dec 7 15:07:26 2017 +0100

    coverity: #1425924

    remove logically dead condition

    Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Coverity's bug analysis is correct but my fix wasn't.

This commit fixes a bunch of other bugs I just spotted as well.

This unblocks #2009.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>