CI: build: add option to disable use of ccache

Add option to disable use of ccache. This can be useful for some
sensible test that should not use ccache as they can cause side effects
of any sort. (example Coverity Scan)

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

.github/workflows/build.yml

@@ -54,6 +54,9 @@ on:
         type: boolean
       upload_external_toolchain:
         type: boolean
+      use_ccache_cache:
+        type: boolean
+        default: true
 
 permissions:
   contents: read
@@ -250,6 +253,7 @@ jobs:
 
       - name: Restore ccache cache
         id: restore-ccache-cache
+        if: inputs.use_ccache_cache == true
         uses: actions/cache/restore@v3
         with:
           path: openwrt/.ccache
@@ -295,6 +299,13 @@ jobs:
           echo CONFIG_TARGET_PER_DEVICE_ROOTFS=y >> .config
           echo CONFIG_TARGET_ALL_PROFILES=y >> .config
 
+      - name: Configure ccache
+        if: inputs.use_ccache_cache == true
+        shell: su buildbot -c "sh -e {0}"
+        working-directory: openwrt
+        run: |
+          echo CONFIG_CCACHE=y >> .config
+
       - name: Configure external toolchain in container
         if: inputs.build_toolchain == false && steps.parse-toolchain.outputs.toolchain-type == 'external_container'
         shell: su buildbot -c "sh -e {0}"
@@ -302,7 +313,6 @@ jobs:
         run: |
           echo CONFIG_DEVEL=y >> .config
           echo CONFIG_AUTOREMOVE=y >> .config
-          echo CONFIG_CCACHE=y >> .config
 
           ./scripts/ext-toolchain.sh \
             --toolchain /external-toolchain/$(ls /external-toolchain/ | grep openwrt-toolchain)/toolchain-* \
@@ -316,7 +326,6 @@ jobs:
         run: |
           echo CONFIG_DEVEL=y >> .config
           echo CONFIG_AUTOREMOVE=y >> .config
-          echo CONFIG_CCACHE=y >> .config
 
           ./scripts/ext-toolchain.sh \
             --toolchain ${{ env.TOOLCHAIN_FILE }}/toolchain-* \
@@ -358,7 +367,6 @@ jobs:
         run: |
           echo CONFIG_DEVEL=y >> .config
           echo CONFIG_AUTOREMOVE=y >> .config
-          echo CONFIG_CCACHE=y >> .config
 
           ./scripts/ext-toolchain.sh \
             --toolchain ${{ env.TOOLCHAIN_FILE }}/staging_dir/toolchain-* \
@@ -372,7 +380,6 @@ jobs:
         run: |
           echo CONFIG_DEVEL=y >> .config
           echo CONFIG_AUTOREMOVE=y >> .config
-          echo CONFIG_CCACHE=y >> .config
 
           echo "CONFIG_TARGET_${{ inputs.target }}=y" >> .config
           echo "CONFIG_TARGET_${{ inputs.target }}_${{ inputs.subtarget }}=y" >> .config
@@ -477,7 +484,7 @@ jobs:
           path: "openwrt/logs"
 
       - name: Delete already present ccache cache
-        if: steps.restore-ccache-cache.outputs.cache-hit == 'true'
+        if: steps.restore-ccache-cache.outputs.cache-hit == 'true' && inputs.use_ccache_cache == true
         uses: octokit/request-action@v2.x
         with:
           route: DELETE /repos/{repository}/actions/caches?key={key}
@@ -487,6 +494,7 @@ jobs:
           INPUT_KEY: ${{ steps.restore-ccache-cache.outputs.cache-primary-key }}
 
       - name: Save ccache cache
+        if: inputs.use_ccache_cache == true
         uses: actions/cache/save@v3
         with:
           path: openwrt/.ccache