dependency on ghostscript. This handles the dependency patterns that will
match either ghostscript{,-nox11} and ghostscript-gnu{,-nox11} depending
on which version number of ghostscript is required. From the comments at
the top of the file:
To use this Makefile fragment, simply:
(1) Optionally set GHOSTSCRIPT_REQD to the minimum version number of
Ghostscript required by the package,
(2) Optionally set USE_GHOSTSCRIPT to "build" to only add a build-time
dependency on Ghostscript,
(3) And include this Makefile fragment in the package Makefile,
