Refactor github workflows; add preprocess test

This commit refactors the github workflows into two
file (push/pull request), makes use of the new central
seL4 github actions, and adds the preprocess test for
pull requests.

Signed-off-by: Gerwin Klein <gerwin.klein@data61.csiro.au>

.github/workflows/git.yaml

@@ -1,39 +0,0 @@
-# Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
-#
-# SPDX-License-Identifier: BSD-2-Clause
-
-name: Git
-
-on: [pull_request]
-
-jobs:
-  gitlint:
-    name: Gitlint
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-      with:
-        fetch-depth: 2
-    - run: |
-        git fetch --depth 1 --no-tags origin +refs/heads/${{ github.base_ref }}:refs/heads/${{ github.base_ref }}
-    - uses: actions/checkout@v2
-      with:
-        repository: seL4/sel4_tools
-        path: sel4_tools
-    - uses: actions/setup-python@v1
-      with:
-        python-version: '3.7'
-    - name: Install gitlint
-      run: pip install gitlint
-    - name: Run gitlint
-      run: gitlint --commits ${{ github.base_ref }}..${{ github.event.pull_request.head.sha }} --config sel4_tools/misc/.gitlint lint
-
-  whitespace:
-    name: Trailing Whitespace
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - run: |
-        git fetch --depth 1 --no-tags origin +refs/heads/${{ github.base_ref }}:refs/heads/${{ github.base_ref }}
-    - name: Check
-      run: git diff --check ${{ github.base_ref }}

.github/workflows/pr.yml

@@ -0,0 +1,46 @@
+# Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
+#
+# SPDX-License-Identifier: BSD-2-Clause
+
+# Actions to run on pull requests
+
+name: PR
+
+on: [pull_request]
+
+jobs:
+  gitlint:
+    name: Gitlint
+    runs-on: ubuntu-latest
+    steps:
+    - uses: seL4/ci-actions/gitlint@master
+
+  whitespace:
+    name: 'Trailing Whitespace'
+    runs-on: ubuntu-latest
+    steps:
+    - uses: seL4/ci-actions/git-diff-check@master
+
+  shell:
+    name: 'Portable Shell'
+    runs-on: ubuntu-latest
+    steps:
+    - uses: seL4/ci-actions/bashisms@master
+
+  style:
+    name: Style
+    runs-on: ubuntu-latest
+    steps:
+    - uses: seL4/ci-actions/style@master
+
+  preprocess:
+    name: Preprocess
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        arch: [ARM, ARM_HYP, RISCV64, X64]
+    steps:
+    - uses: seL4/ci-actions/preprocess@master
+      with:
+        L4V_ARCH: ${{ matrix.arch }}

.github/workflows/push.yml

@@ -2,7 +2,8 @@
 #
 # SPDX-License-Identifier: BSD-2-Clause
 
-name: License
+# Actions to run on Push and Pull Request
+name: CI
 
 on:
   push:
@@ -15,6 +16,10 @@ jobs:
     name: License Check
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
-    - name: Check
-      uses: fsfe/reuse-action@master
+    - uses: seL4/ci-actions/license-check@master
+
+  links:
+    name: Links
+    runs-on: ubuntu-latest
+    steps:
+      - uses: seL4/ci-actions/link-check@master

.github/workflows/style.yaml

@@ -1,47 +0,0 @@
-# Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
-#
-# SPDX-License-Identifier: BSD-2-Clause
-
-name: Style
-
-on:
-  pull_request:
-
-jobs:
-  style:
-    name: Check Style
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - uses: technote-space/get-diff-action@v1
-    - uses: actions/checkout@v2
-      with:
-        repository: seL4/sel4_tools
-        path: sel4_tools
-    - uses: actions/setup-python@v1
-      with:
-        python-version: '3.7'
-    - name: Install python packages
-      run: pip install sel4-deps
-    - name: Install astyle
-      run: sudo apt-get install astyle
-    - name: Run style check
-      run: |
-        sel4_tools/misc/style.sh ${{ env.GIT_DIFF }}
-        [ -z "$(git status -uno --porcelain)" ] || (git diff; exit 1)
-
-  shell:
-    name: Check shell scripts
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - uses: technote-space/get-diff-action@v1
-    - uses: actions/checkout@v2
-      with:
-        repository: seL4/sel4_tools
-        path: sel4_tools
-    - name: Install
-      run: sudo apt-get install devscripts
-    - name: Run shell script check
-      run: |
-        sel4_tools/misc/is-valid-shell-script ${{ env.GIT_DIFF }}