Log Message:
qpdf: Delete reference to libjpeg in the libqpdf `.pc' file

graphics/jpeg does not provide any `.pc' file this will lead in failures when
invoking pkg-config agaisnt `libqpdf'. Adjust `Requires.private:' in
libqpdf.pc.in to omit libjpeg.

Bump PKGREVISION since the new installed libqpdf.pc file will fix packages that
depends on print/qpdf.

OK by <pgoyette> and <ryoon>, thanks!