SCO Openserver supported in 7.3.1

I have worked with Shibashish Satpathy to add support for SCO Openserver
5.0.4 using gcc in 7.3.1.  The port was accomplished via a small change
to template/sco. Seeing as it was an unsupported platform, this is a
no-risk change, because now it _does_ work.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
359-1001+  If your life is a hard drive,     |  13 Roberts Road +  Christ can be your backup.        |  Newtown Square,
Pennsylvania19073