CI: add a github pages job to the CI

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

.github/workflows/pages.yml

@@ -0,0 +1,31 @@
+name: pages
+
+on:
+ push:
+   branches:
+     - master
+
+env:
+  UBUNTU_DEP_BUILD: gcc g++ pkg-config systemd libevdev-dev libglib2.0-dev libjson-glib-dev libsystemd-dev libudev-dev libunistring-dev python3-dev python3-evdev python3-pip swig python3-sphinx python3-sphinx-rtd-theme
+  PIP_PACKAGES: meson ninja
+
+jobs:
+  deploy:
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ./.github/actions/pkginstall
+        with:
+          apt: $UBUNTU_DEP_BUILD
+          pip: $PIP_PACKAGES
+      - name: Build docs
+        uses: ./.github/actions/meson
+        with:
+          meson_args: -Ddocumentation=true -Dtests=false
+          meson_skip_test: yes
+      - name: Deploy to GitHub Pages
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./builddir/doc/html/
+          allow_empty_commit: true