libcupsfilters: Let ghostscript() output Apple Raster directly

libcupsfilters: Let ghostscript() output Apple Raster directly

From version 9.56.0 on Ghostscript support direct Apple Raster (URF)
output.

Therefore now we check via ./configure whether the installed
Ghostscript has an "appleraster" output device and if so, we let the
ghostscript() filter function call Ghostscript using this output
device to directly output Apple Raster, so that we do not need to call
the rastertopwg() filter function any more.

In this case an extra MIME conversion rule taking into account the
Apple Raster output from the gstoraster CUPS filter gets installed and
also the universal() filter function gets built to not call the
rastertopwg() filter function after ghostscript() when Apple Raster
output is requested.