xen: remove 4.5

Depends on a fairly old gcc, marked as insecure for ~2 years.

pkgs/applications/virtualization/xen/packages.nix

@@ -1,62 +1,11 @@
 { callPackage
-, stdenv, overrideCC, gcc49
+, stdenv, overrideCC
 }:
 
 # TODO(@oxij) on new Xen version: generalize this to generate [vanilla slim
 # light] for each ./<version>.nix.
 
 rec {
-
-  xen_4_5-vanilla = callPackage ./4.5.nix {
-    # At the very least included seabios and etherboot need gcc49,
-    # so we have to build all of it with gcc49.
-    stdenv = overrideCC stdenv gcc49;
-
-    meta = {
-      description = "vanilla";
-      longDescription = ''
-        Vanilla version of Xen. Uses forks of Qemu and Seabios bundled
-        with Xen. This gives vanilla experince, but wastes space and
-        build time: typical NixOS setup that runs lots of VMs will
-        build three different versions of Qemu when using this (two
-        forks and upstream).
-      '';
-    };
-  };
-
-  xen_4_5-slim = xen_4_5-vanilla.override {
-    withInternalQemu = false;
-    withInternalTraditionalQemu = true;
-    withInternalSeabios = false;
-    withSeabios = true;
-
-    meta = {
-      description = "slim";
-      longDescription = ''
-        Slimmed-down version of Xen that reuses nixpkgs packages as
-        much as possible. Different parts may get out of sync, but
-        this builds faster and uses less space than vanilla. Use with
-        `qemu_xen` from nixpkgs.
-      '';
-    };
-  };
-
-  xen_4_5-light = xen_4_5-vanilla.override {
-    withInternalQemu = false;
-    withInternalTraditionalQemu = false;
-    withInternalSeabios = false;
-    withSeabios = true;
-
-    meta = {
-      description = "light";
-      longDescription = ''
-        Slimmed-down version of Xen without `qemu-traditional` (you
-        don't need it if you don't know what it is). Use with
-        `qemu_xen-light` from nixpkgs.
-      '';
-    };
-  };
-
   xen_4_8-vanilla = callPackage ./4.8.nix {
     meta = {
       description = "vanilla";