Options in /etc/default/cups can be ignored

[Patrick O'Keeffe]

If the file `/etc/default/cups` does not exist, or it contains `LOAD_LP_MODULE=yes`, then *cups-filters* creates the file `/etc/modules-load.d/cups-filters.conf` with the contents:
```
# Parallel printer driver modules loading for cups
# LOAD_LP_MODULE was 'yes' in /etc/default/cups
lp
ppdev
parport_pc
```

However, if the file `/etc/default/cups` contains `LOAD_LP_MODULE=no` and *cups-filters* has already created the file `/etc/modules-load.d/cups-filters.conf`, then the previous behavior equivalent to `LOAD_LP_MODULE=yes` will persist even after completely reinstalling the *cups-filters* package.

The only solution is to manually remove the file `/etc/modules-load.d/cups-filters.conf`. I think the proper behavior would be for *cups-filters* to remove the file if it exists during installation but `/etc/default/cups` contains `LOAD_LP_MODULE=no`.

[Patrick O'Keeffe (patricktokeeffe)]

Oops almost forgot sorry, running *cups-filters* 1.20.2-0ubuntu3 on Ubuntu Mate 18.04 LTS (4.14.77-v7+)