[SSSD] [sssd PR#508][synchronized] Fix/suppress few gcc8 warnings

[lslebodn]

   URL: https://github.com/SSSD/sssd/pull/508
Author: lslebodn
 Title: #508: Fix/suppress few gcc8 warnings
Action: synchronized

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/508/head:pr508
git checkout pr508