cyan: fix cmake-4 build failure

Without the change the build fails on `master` as
https://hydra.nixos.org/build/311319725:

    CMake Error at CMakeLists.txt:31 (cmake_minimum_required):
      Compatibility with CMake < 3.5 has been removed from CMake.

ZHF: #457852

pkgs/by-name/cy/cyan/package.nix

@@ -2,6 +2,7 @@
   lib,
   stdenv,
   fetchFromGitHub,
+  fetchpatch2,
   qt5,
   cmake,
   pkg-config,
@@ -20,6 +21,16 @@ stdenv.mkDerivation rec {
     hash = "sha256-R5sj8AN7UT9OIeUPNrdTIUQvtEitXp1A32l/Z2qRS94=";
   };
 
+  patches = [
+    # cmake-4 build fix:
+    #   https://github.com/rodlie/cyan/pull/123
+    (fetchpatch2 {
+      name = "cmake-4.patch";
+      url = "https://github.com/rodlie/cyan/commit/885e81310de8df7f32a5e1d2c722f89bcd969cd1.patch?full_index=1";
+      hash = "sha256-5VhXKamDNGeEvi86l+R3Lvzb4G5JFBq2dqqd6TdyxZ4=";
+    })
+  ];
+
   nativeBuildInputs = [
     cmake
     pkg-config