ghostscript: Update version to 9.54.0

ghostscript: Update version to 9.54.0

- Update from 9.53.3 to 9.54.0
- Update rootfile
- delete patch related to FT_CALLBACK_DEF as fix has been implemented in the source
   tarball
- Changelog highlights
   Version 9.54.0 (2021-03-30)
     The 9.54.0 release is a maintenance release, and also adds new functionality.
     Highlights in this release include:
       Overprint simulation is now available to all output devices, allowing quality previewing/proofing of PostScript and PDF jobs that rely on overprint. See the -dOverprint option documentation in: Overprint
       The "docxwrite" device adds the ability to output to Microsoft Word "docx" format. See: docxwrite
       The pdfwrite device is now capable of using the Tesseract OCR engine when it is built into Ghostscript to improve searchability and copy and paste functionality when the input lacks the metadata for that purpose. See: UseOCR
       Ghostscript/GhostPDL now includes a "map text to black" function, where text drawn by an input job (except when drawn using a Type 3 font) can be forced to draw in solid black. See: BlackText
       Ghostscript/GhostPDL now supports simple N-up imposition "internally". See: NupControl
       Our efforts in code hygiene and maintainability continue.
       The usual round of bug fixes, compatibility changes, and incremental improvements.
   Full details of above highlights can be found at https://www.ghostscript.com/doc/9.54.0/History9.htm

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>