Remove myself (fuuzetsu) from maintainer lists

I haven't been doing any maintenance for a long time now and not only
do I get notified, it also creates a fake impression that all these
packages had at least one maintainer when in practice they had none.

pkgs/development/libraries/libpng/12.nix

@@ -24,7 +24,7 @@ stdenv.mkDerivation rec {
     description = "The official reference implementation for the PNG file format";
     homepage = http://www.libpng.org/pub/png/libpng.html;
     license = licenses.libpng;
-    maintainers = [ maintainers.fuuzetsu ];
+    maintainers = [ ];
     branch = "1.2";
     platforms = platforms.unix;
   };

pkgs/development/libraries/libpng/default.nix

@@ -34,6 +34,6 @@ in stdenv.mkDerivation rec {
     homepage = http://www.libpng.org/pub/png/libpng.html;
     license = licenses.libpng2;
     platforms = platforms.all;
-    maintainers = [ maintainers.vcunat maintainers.fuuzetsu ];
+    maintainers = [ maintainers.vcunat ];
   };
 }