New comment by maop on void-packages repository

https://github.com/void-linux/void-packages/issues/28664#issuecomment-787212410

Comment:
While we wait for the maintainer, you can add the following to your ~/.local/share/applications/xpdf.desktop

```
[Desktop Entry]
Name=xpdf
GenericName=PDF viewer
Comment=View PDF files
Exec=xpdf %f
Icon=xpdf
Terminal=false
Type=Application
MimeType=application/pdf;application/x-pdf;application/x-gzpdf;application/x-bzpdf;application/x-xzpdf;application/x-lzpdf;
Categories=Viewer;Graphics;
Keywords=Viewer;Graphics;
```