Fix TLogger.AddStdLine to work with Wine 1.6

Fix TLogger.AddStdLine to work with Wine 1.6

Wine 1.6 gives a standard output handle to the service process,
albeit all writes to it fails. Because of this, TLogger.AddStdLine
did not even write to the log file due to short-circuit evaluation.
Now I made sure to attempt both stdout and logfile writes.

Native Windows doesn't provide an stdout handle for service processes
(GetStdHandle returns 0), in which case MgSMTP detects it has no
stdout and redirects its output to mgsmtp_stdout.log. Wine 3.0 behaves
the same, so I deemed the Wine 1.6 behaviour a bug. Therefore, I find
this quick fix sufficient - there is no need to bother with Wine 1.6
compatibility any further, e.g. by checking if Wine 1.6 gave a writable
stdout handle or not. Users of MgSMTP on Wine are rather suggested to
update to Wine 3.0.

	modified:   Log.pas
	modified:   MgSMTP.pas