[SSSD] [sssd PR#710][opened] data_provider_fo: fix error in hostname retrieval

[alexey-tikhonov]

   URL: https://github.com/SSSD/sssd/pull/710
Author: alexey-tikhonov
 Title: #710: data_provider_fo: fix error in hostname retrieval
Action: opened

PR body:
"""
Fixed off-by-one error in gethostname() param

Resolves:
https://pagure.io/SSSD/sssd/issue/3865
"""

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/710/head:pr710
git checkout pr710