Add github action to sync kernel-mainline

This github action will sync the kernel-mainline branch with Linus'
tree every day at 8am

LE-2708

Author: bmastbergen

.github/workflows/sync.yml

@@ -0,0 +1,51 @@
+name: Kernel Sync
+
+on:
+  schedule:
+    - cron: "0 8 * * *"
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    container:
+      image: rockylinux:9
+    strategy:
+      fail-fast: false
+      matrix:
+         include:
+           - branch: kernel-mainline
+             remote: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
+             remote_branch: master
+
+    env:
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      BRANCH: ${{ matrix.branch }}
+      REMOTE: ${{ matrix.remote }}
+      REMOTE_BRANCH: ${{ matrix.remote_branch }}
+
+    steps:
+      - name: Install git
+        run: |
+          dnf install -y git
+
+      - name: Check out repository
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ env.BRANCH }}
+          path: ${{ env.BRANCH }}
+
+      - name: Sync kernel source
+        working-directory: ./${{ env.BRANCH }}
+        run: |
+          set -e
+
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+          git remote add upstream ${REMOTE}
+          git fetch upstream --tags --quiet
+          git rebase upstream/${REMOTE_BRANCH}
+          git push origin --follow-tags
+
+