btrfs-progs: drop upstreamed patch

Without the change `btrfs-progs` fails to build after `6.9` update on
`staging-next` as:

       > Skipping patch.
       > 2 out of 2 hunks ignored -- saving rejects to file convert/source-ext2.c.rej

The patch was already included in this release. Dropping.

pkgs/tools/filesystems/btrfs-progs/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, fetchpatch
+{ lib, stdenv, fetchurl
 , buildPackages
 , pkg-config
 , zstd
@@ -17,14 +17,6 @@ stdenv.mkDerivation rec {
     hash = "sha256-fhSl1ZfzI919G0U+Ok5mGn6fB+oGDvv/T3b/gxWRfeg=";
   };
 
-  patches = [
-    # backport fix build with e2fsprogs 1.47.1
-    (fetchpatch {
-      url = "https://github.com/kdave/btrfs-progs/commit/bcb887a4de2c56426a7a7de8d440b6ad75579f10.patch";
-      hash = "sha256-Ir5EiiU0E8GBnGex0Q/WTNexW9XTWFNceiLQvXygIoo=";
-    })
-  ];
-
   nativeBuildInputs = [
     pkg-config
   ] ++ [