qt3, graphicsmagick137, fox, neverball: fix build

Broken after freetype propagating libpng, which hid the older ones.
Reordering is enough to ensure the older libpng gets picked.

pkgs/applications/graphics/graphicsmagick/1.3.7.nix

···
   configureFlags = "--enable-shared";
 
   buildInputs =
-    [ bzip2 freetype ghostscript graphviz libjpeg libpng libtiff libX11 libxml2
+    [ libpng bzip2 freetype ghostscript graphviz libjpeg libtiff libX11 libxml2
       zlib libtool
     ];
 

pkgs/development/libraries/fox/default.nix

···
     md5 = "b5897e9c664967f5042e57070037ff18";
   };
 
-  buildInputs = [ x11 libpng libjpeg libtiff zlib bzip2 libXcursor libXrandr libXft ];
+  buildInputs = [ libpng x11 libjpeg libtiff zlib bzip2 libXcursor libXrandr libXft ];
 
   doCheck = true;
 

pkgs/development/libraries/qt-3/default.nix

···
   };
 
   nativeBuildInputs = [ which ];
-  propagatedBuildInputs = [x11 libXft libXrender zlib libjpeg libpng];
+  propagatedBuildInputs = [libpng x11 libXft libXrender zlib libjpeg];
 
   configureFlags = "
     -v

pkgs/games/neverball/default.nix

···
     sha256 = "19hdgdmv20y56xvbj4vk0zdmyaa8kv7df85advkchw7cdsgwlcga";
   };
 
-  buildInputs = [ SDL mesa libpng libjpeg SDL_ttf libvorbis gettext physfs];
+  buildInputs = [ libpng SDL mesa libjpeg SDL_ttf libvorbis gettext physfs];
 
   dontPatchElf = true;