cygwin-pkg-maint cleanup

[Jon Turney]

I've done another clean-up of cygwin-pkg-maint, removing those source 
packages names which no longer exist after x86 was archived (i.e only 
existed as x86 packages)

> cygwin64-*       ORPHANED (Yaakov Selkowitz) 32-bit only by design
> db4.8            OBSOLETE (Dr. Volker Zell)  Obsoletion by db 5.x was done in an unusual way
> gnome-characters ORPHANED (Yaakov Selkowitz) Presumably build problems on x64. Whole GNOME stack needs looking at
> hdparm           ORPHANED (Christian Franke) Presumably build problems on x64. Cygwin-specific port of hdparm
> sushi            ORPHANED (Yaakov Selkowitz) Presumably build problems on x64. GNOME file manager previewer. Whole GNOME stack needs looking at
> xemacs           ORPHANED (Dr. Volker Zell)  Is it dead yet?
> xemacs-mule-sumo ORPHANED (Dr. Volker Zell)  ditto
> xemacs-sumo      ORPHANED (Dr. Volker Zell)  ditto
> xview            Jon Turney                  32-bit only by design

Note that a lot of long obsolete install package names have also 
disappeared (e.g. ash, which was obsoleted by dash in 2009, etc.)