feat: compat code for non x86_64-linux

- do not build packages, which require `x86_64-linux`
- use Phala `dcap-qvl` crate for remote attestation, if possible
- nix: exclude `nixsgx` on non `x86_64-linux` platforms

Signed-off-by: Harald Hoyer <[email protected]>

Author: haraldh

.github/workflows/nix-non-x86.yml

@@ -0,0 +1,35 @@
+name: nix-non-x86
+
+permissions:
+  contents: read
+  pull-requests: read
+
+on:
+  pull_request:
+    branches: ["main"]
+  push:
+    branches: ["main"]
+    tags: ["*"]
+
+jobs:
+  macos-latest:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+      - uses: cachix/install-nix-action@v30
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ github.token }}
+            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= tee-pot:SS6HcrpG87S1M6HZGPsfo7d1xJccCGev7/tXc5+I4jg=
+            substituters = https://cache.nixos.org/ https://attic.teepot.org/tee-pot
+            sandbox = true
+      - name: Setup Attic cache
+        uses: ryanccn/attic-action@v0
+        with:
+          endpoint: https://attic.teepot.org/
+          cache: tee-pot
+          token: ${{ secrets.ATTIC_TOKEN }}
+
+      - name: nixci
+        run: nix run nixpkgs#nixci -- build
+