...for regenerating slanted symbol font.
* font/devpdf/generate/Makefile: New file (re)creates AFM and PFB files
for slanted symbol font from SFD source. We emplace the files with
".in" suffixes so that they'll work with the groff build process in
both in-tree and out-of-tree scenarios.
* font/devpdf/generate/symbolsl.sfd: Update metadata to credit Deri with
modifications.
* font/devpdf/symbolsl.pfb.in: Refresh using foregoing Makefile.
* font/devpdf/symbolsl.afm.in: New file, generated by foregoing
Makefile.