surface: Fix kernel 6.1.18 by removing 0015-intel-thread-director.patch

[ifd3f]

Description of changes

The latest version of linux-surface does not contain 0015-intel-thread-director.patch. This was breaking the 6.1.x kernel build like so:

       > Hunk #3 succeeded at 1314 (offset -5 lines).
       > patching file arch/x86/kernel/acpi/boot.c
       > Hunk #1 succeeded at 1250 (offset -5 lines).
       > applying patch /nix/store/paasl6sbph09j5vm169307k2qzmrwd5c-source/patches/6.1/0014-rtc.patch
       > patching file drivers/acpi/acpi_tad.c
       > applying patch /nix/store/paasl6sbph09j5vm169307k2qzmrwd5c-source/patches/6.1/0015-intel-thread-director.patch
       > /nix/store/vfdg65hiv4bwls48588msw8la7452w2q-stdenv-linux/setup: line 1216: /nix/store/paasl6sbph09j5vm169307k2qzmrwd5c-source/patches/6.1/0015-intel-thread-director.patch: No such file or directory
       For full logs, run 'nix log /nix/store/jshzbq97k8ayrh99m88bzxz9r7nnlbyq-linux-config-6.1.18.drv'.
error: 1 dependencies of derivation '/nix/store/yrlnq1riv3w98jkr12ix6xlhyxvw4xcl-linux-6.1.18.drv' failed to build

Things done

Successfully built nixos configuration at flake github:ifd3f/infra/surface-unbreak#shai-hulud, which uses input github:ifd3f/nixos-hardware/remove-intel-thread-director and kernel 6.1.18.

• Tested the changes in your own NixOS Configuration
• Tested the changes end-to-end by using your fork of nixos-hardware and
  importing it via Flake input