cleaning up VMS chapter in manual

[Douglas B Rupp]

The include file stuff is certainly N/A for Gnu C on Alpha/VMS.

However I think the globalref globaldef stuff is still applicable. It's used in our Alpha/VMS port of GDB, which is
currently built with
Compaq C but may (someday) be built with Gnu C.  The examples in the VMS chapter at least compile with Gnu C.

--Douglas Rupp
Ada Core Technologies, Inc

> Comments solicited on my patch!  Gerald Pfeiffer has approved it unless
> someone says something, so if there's a problem please say something!!