Azure/GitLab CI: Add the pylint checker

Add a check that new Python code does not regress the pylint score for
any module.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
index db45291..8352b10 100644
--- a/.azure-pipelines.yml
+++ b/.azure-pipelines.yml
@@ -202,6 +202,28 @@
           export PATH=/opt/gcc-11.1.0-nolibc/arm-linux-gnueabi/bin:$PATH
           test/nokia_rx51_test.sh
 
+  - job: pylint
+    displayName: Check for any pylint regressions
+    pool:
+      vmImage: $(ubuntu_vm)
+    container:
+      image: $(ci_runner_image)
+      options: $(container_option)
+    steps:
+      - script: |
+          cd ${WORK_DIR}
+          export USER=azure
+          pip install -r test/py/requirements.txt
+          pip install asteval pylint pyopenssl
+          export PATH=${PATH}:~/.local/bin
+          echo "[MASTER]" >> .pylintrc
+          echo "load-plugins=pylint.extensions.docparams" >> .pylintrc
+          export UBOOT_TRAVIS_BUILD_DIR=/tmp/sandbox_spl
+          ./tools/buildman/buildman -T0 -o ${UBOOT_TRAVIS_BUILD_DIR} -w --board sandbox_spl
+          pylint --version
+          export PYTHONPATH=${UBOOT_TRAVIS_BUILD_DIR}/scripts/dtc/pylibfdt
+          make pylint_err
+
 - stage: test_py
   jobs:
   - job: test_py