squashfsTools: 4.4dev_20180612 -> 4.4

A new release has been made upstream. Reproducibility issues were fixed
in that release, so we no longer need those patches. For a full overview
of the changes, see the 4.4-specific readme at [1].

The alignment patch no longer applies cleanly; I disabled it for now,
and I will try to restore it in a follow-up commit.

[1]: https://github.com/plougher/squashfs-tools/blob/52eb4c279cd283ed9802dd1ceb686560b22ffb67/README-4.4

pkgs/tools/filesystems/squashfs/default.nix

@@ -8,26 +8,21 @@ assert lz4Support -> (lz4 != null);
 
 stdenv.mkDerivation {
   pname = "squashfs";
-  version = "4.4dev_20180612";
+  version = "4.4";
 
   src = fetchFromGitHub {
     owner = "plougher";
     repo = "squashfs-tools";
-    sha256 = "1y53z8dkph3khdyhkmkmy0sg9p1n8czv3vj4l324nj8kxyih3l2c";
-    rev = "6e242dc95485ada8d1d0b3dd9346c5243d4a517f";
+    sha256 = "0697fv8n6739mcyn57jclzwwbbqwpvjdfkv1qh9s56lvyqnplwaw";
+    # Tag "4.4" points to this commit.
+    rev = "52eb4c279cd283ed9802dd1ceb686560b22ffb67";
   };
 
   patches = [
-    # These patches ensures that mksquashfs output is reproducible.
-    # See also https://reproducible-builds.org/docs/system-images/
-    # and https://github.com/NixOS/nixpkgs/issues/40144.
-    ./0001-If-SOURCE_DATE_EPOCH-is-set-override-timestamps-with.patch
-    ./0002-If-SOURCE_DATE_EPOCH-is-set-also-clamp-content-times.patch
-    ./0003-remove-frag-deflator-thread.patch
-
     # This patch adds an option to pad filesystems (increasing size) in
     # exchange for better chunking / binary diff calculation.
-    ./squashfs-tools-4.4-4k-align.patch
+    # TODO(ruuda): make this patch apply to the proper 4.4 release.
+    # ./squashfs-tools-4.4-4k-align.patch
   ] ++ stdenv.lib.optional stdenv.isDarwin ./darwin.patch;
 
   buildInputs = [ zlib xz zstd ]