Bug#1015908: src: qpdfview: remove vendored synctex code and use Debian package instead

[Louis-Philippe Véronneau]

Package: src:qpdfview
Version: 0.4.18-8
Severity: normal
Upstream very helpfully pointed out we're using the vendored synctex 
code that they use instead of using the Debian package:

https://packages.debian.org/sid/libsynctex-dev

We should exclude that code from the upstream tarball and use the Debian 
package instead :)

[1]: https://bugs.launchpad.net/bugs/1982665

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  ⢀⣴⠾⠻⢶⣦⠀
  ⣾⠁⢠⠒⠀⣿⡁  Louis-Philippe Véronneau
  ⢿⡄⠘⠷⠚⠋   po...@debian.org / veronneau.org
  ⠈⠳⣄