We don't install PAM services anymore

[Martin Gräßlin]

Hi,

I just noticed that since we did the kde-workspace repo split we no 
longer install the PAM service files.

This used to be done by: 
https://cgit.kde.org/kde-workspace.git/tree/mkpamserv?h=KDE/4.11 and the 
pam service file is 
https://cgit.kde.org/kde-workspace.git/tree/kde.pamd?h=KDE/4.11

kcheckpass still references this, but the pam service file does not 
exist.

Given that this has been broken now for several years and nobody 
complained or noticed, I think we don't need to fix it.

Opinions?

Cheers
Martin