treewide: Make explicit that 'dev' output of poppler is used

pkgs/applications/editors/texmaker/default.nix

···
 
   buildInputs = [ qt4 poppler_qt4 zlib ];
   nativeBuildInputs = [ pkgconfig poppler qmake4Hook ];
-  NIX_CFLAGS_COMPILE="-I${poppler}/include/poppler";
+  NIX_CFLAGS_COMPILE="-I${poppler.dev}/include/poppler";
 
   preConfigure = ''
     qmakeFlags="$qmakeFlags DESKTOPDIR=$out/share/applications ICONDIR=$out/share/pixmaps"

pkgs/applications/misc/apvlv/default.nix

···
   };
 
   preConfigure = ''
-    export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -I${poppler}/include/poppler"
+    export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -I${poppler.dev}/include/poppler"
   '';
 
   buildInputs = [