Apply RTF fixups which improves our .rtf generation:
- Tell the location where Jade/OpenJade will look for the PNG images.
- Use rtf-nopng as extension name for Jade/OpenJade generated RTF files.
- Use fixrtf(1) from textproc/fixrtf to make necessary fixups on generated RTFs, embedding PNGs into the intermediate RTF and save them into the new *.rtf files.
- Retire rtf.tar target which is no longer necessary.
Please note that you have to upgrade the docproj toolset or
this commit would break the build.
PR: docs/93965
Submitted by: intron <intron intron ac>
Approved by: doceng