deepin: remove from nixpkgs

The Deepin Desktop Environment (DDE) is not yet fully packaged in
nixpkgs and it has shown a very difficult task to complete, as
discussed in https://github.com/NixOS/nixpkgs/issues/94870. The
conclusion is that it is better to completely remove it.

pkgs/tools/networking/zssh/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, readline, deepin }:
+{ stdenv, fetchurl, readline }:
 
 let
   version = "1.5c";
@@ -33,7 +33,7 @@ in stdenv.mkDerivation rec {
     description = "SSH and Telnet client with ZMODEM file transfer capability";
     homepage = "http://zssh.sourceforge.net/";
     license = stdenv.lib.licenses.gpl2;
-    maintainers = deepin.deepin-terminal.meta.maintainers; # required by deepin-terminal
+    maintainers = [ ]; # required by deepin-terminal
     platforms = stdenv.lib.platforms.linux;
   };
 }