CI: kernel: check if patch are refreshed for each target

Enforce refreshed patch for each target with kernel pr tests.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

.github/workflows/kernel.yml

@@ -213,3 +213,74 @@ jobs:
         with:
           name: ${{ env.TARGET }}-${{ env.SUBTARGET }}-logs
           path: "openwrt/logs"
+
+  check-patch:
+    name: Check Kernel patches
+    needs: determine_targets
+    runs-on: ubuntu-latest
+    strategy:
+       fail-fast: False
+       matrix:
+         target: ${{fromJson(needs.determine_targets.outputs.target)}}
+
+    container: ghcr.io/${{ needs.determine_targets.outputs.owner_lc }}/tools:latest
+
+    permissions:
+      contents: read
+      packages: read
+
+    steps:
+      - name: Checkout master directory
+        uses: actions/checkout@v3
+        with:
+          path: openwrt
+
+      - name: Fix permission
+        run: |
+          chown -R buildbot:buildbot openwrt
+
+      - name: Initialization environment
+        run: |
+          TARGET=$(echo ${{ matrix.target }} | cut -d "/" -f 1)
+          SUBTARGET=$(echo ${{ matrix.target }} | cut -d "/" -f 2)
+          echo "TARGET=$TARGET" >> "$GITHUB_ENV"
+          echo "SUBTARGET=$SUBTARGET" >> "$GITHUB_ENV"
+
+      - name: Extract prebuilt tools
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: ./scripts/ext-tools.sh --tools /tools.tar
+
+      - name: Setup Config
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: |
+          echo CONFIG_ALL_KMODS=y >> .config
+          echo CONFIG_DEVEL=y >> .config
+          echo CONFIG_AUTOREMOVE=y >> .config
+          echo CONFIG_CCACHE=y >> .config
+
+          echo "CONFIG_TARGET_${{ env.TARGET }}=y" >> .config
+          echo "CONFIG_TARGET_${{ env.TARGET }}_${{ env.SUBTARGET }}=y" >> .config
+
+          make defconfig
+
+      - name: Build tools
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: make tools/quilt/compile -j$(nproc) BUILD_LOG=1 || ret=$? .github/workflows/scripts/show_build_failures.sh
+
+      - name: Refresh Kernel patches
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: |
+          make target/linux/refresh V=s
+
+          . .github/workflows/scripts/ci_helpers.sh
+
+          if git diff --name-only --exit-code; then
+            success "Kernel patches for ${{ env.TARGET }}/${{ env.SUBTARGET }} seems ok"
+          else
+            err "Kernel patches for ${{ env.TARGET }}/${{ env.SUBTARGET }} require refresh. (run 'make target/linux/refresh' and force push this pr)"
+            exit 1
+          fi