[Samba] matchname: host name/name mismatch logging

[Michael Tokarev]

After fixing the abnormal logging with attempts to chmod smbpasswd file,
a new threat is now happening:

[2024/01/10 16:29:13.984400,  0, pid=2853904] ../../source3/lib/util_sock.c:711(matchname)
   matchname: host name/name mismatch: 10.2.111.26 != (NULL)
[2024/01/10 16:29:13.984471,  0, pid=2853904] ../../source3/lib/util_sock.c:893(get_remote_hostname)
   matchname failed on 10.2.111.26

Yes, we've enabled hostname lookups, for a reason.  But this logging is ridiculous anyway,
especially in this form when there's *no* rDNS for the given IP.  I can understand a log
entry with debug priority if rDNS *mismatches*, but not when there's *no* rDNS.  And this
is logged with level=1!

Sigh..

/mjt