[SSSD] [sssd PR#677][comment] WIP pcre: port to pcre2

[thalman]

URL: https://github.com/SSSD/sssd/pull/677
Title: #677: WIP pcre: port to pcre2

thalman commented:
"""
@jhrozek Please take a look at this update. Let me know if I get your suggestion right and I wil rebase it to one commit.
"""

See the full comment at https://github.com/SSSD/sssd/pull/677#issuecomment-446977151