[Freeipa-devel] [freeipa PR#578][comment] Coverity: fix bad use of null-like value in cert.py

[MartinBasti]

  URL: https://github.com/freeipa/freeipa/pull/578
Title: #578: Coverity: fix bad use of null-like value in cert.py

MartinBasti commented:
"""
I would rather focus on why `principal_obj` is not defined there
"""

See the full comment at https://github.com/freeipa/freeipa/pull/578#issuecomment-286216443