[openwrt/openwrt] CI: use tools:latest container to speedup kernel workflow

[LEDE Commits]

ansuel pushed a commit to openwrt/openwrt.git, branch openwrt-21.02:
https://git.openwrt.org/f4db2752500bb4fcc8a1bad586b192dc186d30a1

commit f4db2752500bb4fcc8a1bad586b192dc186d30a1
Author: Christian Marangi <ansuelsmth at gmail.com>
AuthorDate: Mon Sep 5 23:18:00 2022 +0200

    CI: use tools:latest container to speedup kernel workflow
    
    Use tools:latest container with prebuilt host tools to speedup kernel
    compilation in kernel workflow.
    
    Signed-off-by: Christian Marangi <ansuelsmth at gmail.com>
    (cherry picked from commit 5d09118f8e60fa151e03916f255f5511e197af68)
---
 .github/workflows/kernel.yml | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/kernel.yml b/.github/workflows/kernel.yml
index 5afd546394..5589610d08 100644
--- a/.github/workflows/kernel.yml
+++ b/.github/workflows/kernel.yml
@@ -53,7 +53,11 @@ jobs:
        matrix:
          target: ${{fromJson(needs.determine_targets.outputs.target)}}
 
-    container: registry.gitlab.com/openwrt/buildbot/buildworker-3.4.1
+    container: ghcr.io/${{ github.repository_owner }}/tools:latest
+
+    permissions:
+      contents: read
+      packages: read
 
     steps:
       - name: Checkout master directory
@@ -129,19 +133,24 @@ jobs:
           wget -O - https://downloads.cdn.openwrt.org/snapshots/targets/${{ env.TARGET }}/${{ env.SUBTARGET }}/${TOOLCHAIN_FILE}.tar.xz \
             | tar --xz -xf -
 
+      - name: Extract prebuilt tools
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: ./scripts/ext-tools.sh --tools /tools.tar
+
       - name: Configure external toolchain
         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
 
           ./scripts/ext-toolchain.sh \
             --toolchain ${{ env.TOOLCHAIN_FILE }}/toolchain-* \
             --overwrite-config \
             --config ${{ env.TARGET }}/${{ env.SUBTARGET }}
 
-          make defconfig
-
       - name: Show configuration
         shell: su buildbot -c "sh -e {0}"
         working-directory: openwrt