systemd: 255.4 -> 255.6

pkgs/os-specific/linux/systemd/default.nix

@@ -5,7 +5,6 @@
 , nixosTests
 , pkgsCross
 , fetchFromGitHub
-, fetchpatch
 , fetchzip
 , buildPackages
 , makeBinaryWrapper
@@ -180,7 +179,7 @@ assert withBootloader -> withEfi;
 let
   wantCurl = withRemote || withImportd;
   wantGcrypt = withResolved || withImportd;
-  version = "255.4";
+  version = "255.6";
 
   # Use the command below to update `releaseTimestamp` on every (major) version
   # change. More details in the commentary at mesonFlags.
@@ -198,7 +197,7 @@ stdenv.mkDerivation (finalAttrs: {
     owner = "systemd";
     repo = "systemd-stable";
     rev = "v${version}";
-    hash = "sha256-P1mKq+ythrv8MU7y2CuNtEx6qCDacugzfsPRZL+NPys=";
+    hash = "sha256-ah0678iNfy0c5NhHhjn0roY6RoM8OE0hWyEt+qEGKRQ=";
   };
 
   # On major changes, or when otherwise required, you *must* :
@@ -229,15 +228,6 @@ stdenv.mkDerivation (finalAttrs: {
     ./0017-meson.build-do-not-create-systemdstatedir.patch
   ] ++ lib.optional (stdenv.hostPlatform.isLinux && stdenv.hostPlatform.isGnu) [
     ./0018-timesyncd-disable-NSCD-when-DNSSEC-validation-is-dis.patch
-  ] ++ lib.optional (stdenv.hostPlatform.isPower || stdenv.hostPlatform.isRiscV || stdenv.hostPlatform.isMips) [
-    # Fixed upstream and included in the main and stable branches. Can be dropped
-    # when bumping to >= v255.5.
-    # https://github.com/systemd/systemd/issues/30448
-    # https://github.com/NixOS/nixpkgs/pull/282607
-    (fetchpatch {
-      url = "https://github.com/systemd/systemd/commit/8040fa55a1cbc34dede3205a902095ecd26c21e3.patch";
-      sha256 = "0c6z7bsndbkb8m130jnjpsl138sfv3q171726n5vkyl2n9ihnavk";
-    })
   ] ++ lib.optional stdenv.hostPlatform.isMusl (
     let
       oe-core = fetchzip {