Add gitlab-ci

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>

.gitlab-ci.yml

+variables:
+  APT_OPTIONS: -y --allow-unauthenticated
+  ARCH: arm64
+  CROSS_COMPILE: aarch64-linux-gnu-
+  CCACHE_BASEDIR: $CI_PROJECT_DIR
+  CCACHE_DIR: $CI_PROJECT_DIR/ccache
+
+stages:
+  - build
+
+# Retry jobs after runner system failures
+.retry: &retry
+  retry:
+    max: 2
+    when:
+      - runner_system_failure
+
+build:
+  stage: build
+  image: debian:testing
+  cache:                                                             
+    paths:                                                                                                 
+      - ccache
+  before_script:
+    - echo "deb  http://deb.debian.org/debian testing main contrib non-free" > /etc/apt/sources.list
+    - echo "deb-src http://deb.debian.org/debian testing main contrib non-free" >> /etc/apt/sources.list
+    - apt-get update && apt-get $APT_OPTIONS build-dep linux && apt-get $APT_OPTIONS install devscripts ccache fakeroot gcc-aarch64-linux-gnu g++-aarch64-linux-gnu
+  script:
+    - export PATH="/usr/lib/ccache:$PATH"
+    - ccache -s
+    - make imx_v8_defconfig
+    - make -j$(nproc) bindeb-pkg
+    - mkdir artifacts && dcmd mv ../*.changes artifacts/
+  artifacts:
+    name: debs
+    paths:
+      - $CI_PROJECT_DIR/artifacts/*.deb