pdf2djvu: ignore windres on linux to fix build

https://github.com/NixOS/nixpkgs/pull/30484#issuecomment-345899910

+5
+5
pkgs/tools/typesetting/pdf2djvu/default.nix
··· 15 15 16 16 preConfigure = '' 17 17 sed -i 's#\$djvulibre_bin_path#${djvulibre.bin}/bin#g' configure 18 + 19 + # Configure skips the failing check for usability of windres when it is nonempty. 20 + unset WINDRES 18 21 ''; 22 + 23 + enableParallelBuilding = true; 19 24 20 25 meta = with stdenv.lib; { 21 26 description = "Creates djvu files from PDF files";