Merge branch 'jk/ident-ai-canonname-could-be-null'

In the codepath that comes up with the hostname to be used in an
e-mail when the user didn't tell us, we looked at ai_canonname
field in struct addrinfo without making sure it is not NULL first.

* jk/ident-ai-canonname-could-be-null:
  ident: handle NULL ai_canonname

diff --cc ident.c
Simple merge