Warning message when starting outlook

* src/oemhlp.cpp: exit direct from log_addins if debug is disabled

We don't need to run this code if we don't
output the result in the logfile. This prevents an outlook msgbox
from poping up if the following regkey is set when calling
get_oom_object(.., "COMAddins") :
[HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\
common\privacy]
"disconnectedstate"=dword:00000002

• GnuPG-Bug-Id: T8036