wlx-overlay-s: make openvr support optional, disable on aarch64-linux

wlx-overlay-s uses
https://github.com/galister/ovr_overlay_oyasumi/pull/2, which pulls in a
version of ovr_overlay_sys with a build.rs file that doesn't build on
aarch64-linux.

https://github.com/galister/ovr_overlay_oyasumi is a fork of
https://github.com/Raphiiko/ovr_overlay_oyasumi, which is a fork of
https://github.com/TheButlah/ovr_overlay, with the latter not updated in
two years.

Luckily openvr is kinda discouraged, and openxr is the new kid on the
block, and openvr support can be feature-flagged out.

So let's do this, by adding a withOpenVr option to the derivation, that
defaults to false on aarch64-linux, unbreaking it there.

We still keep openvr support for x86_64-linux enabled, to not regress
experience for people already using openvr on x86_64-linux.

pkgs/by-name/wl/wlx-overlay-s/package.nix

@@ -22,6 +22,8 @@
   testers,
   wayland,
   wlx-overlay-s,
+  # openvr support is broken on aarch64-linux
+  withOpenVr ? !stdenv.hostPlatform.isAarch64,
 }:
 
 rustPlatform.buildRustPackage rec {
@@ -37,6 +39,17 @@ rustPlatform.buildRustPackage rec {
 
   cargoHash = "sha256-em5sWSty2/pZp2jTwBnLUIBgPOcoMpwELwj984XYf+k=";
 
+  # explicitly only add openvr if withOpenVr is set to true.
+  buildNoDefaultFeatures = true;
+  buildFeatures = [
+    "openxr"
+    "osc"
+    "x11"
+    "wayland"
+    "wayvr"
+  ]
+  ++ lib.optional withOpenVr "openvr";
+
   nativeBuildInputs = [
     makeWrapper
     pkg-config
@@ -52,11 +65,11 @@ rustPlatform.buildRustPackage rec {
     libXext
     libXrandr
     libxkbcommon
-    openvr
     openxr-loader
     pipewire
     wayland
-  ];
+  ]
+  ++ lib.optional withOpenVr openvr;
 
   env.SHADERC_LIB_DIR = "${lib.getLib shaderc}/lib";
 
@@ -79,7 +92,7 @@ rustPlatform.buildRustPackage rec {
     license = lib.licenses.gpl3Only;
     maintainers = with lib.maintainers; [ Scrumplex ];
     platforms = lib.platforms.linux;
-    broken = stdenv.hostPlatform.isAarch64;
+    broken = stdenv.hostPlatform.isAarch64 && withOpenVr;
     mainProgram = "wlx-overlay-s";
   };
 }