github: always test Xen

We want to make sure Xen related workflows are not broken in the future.
As github workflows offer 6h runtime, this is a good opportunity.
Furthermore, setup and usage is simple.

The current state of the file adds compiling CBMC, as well as getting
Xen. We will add next steps incrementally.

Signed-off-by: Norbert Manthey <nmanthey@amazon.de>

CR: https://code.amazon.com/reviews/CR-28954277

Author: nmanthey

.github/workflows/build-and-test-Xen.yml

@@ -0,0 +1,26 @@
+name: Build and Test Xen
+
+on: [push]
+
+jobs:
+  Linux:
+
+    runs-on: ubuntu-18.04
+
+    steps:
+    - name: Install Packages
+      run: sudo apt-get install coreutils \
+        build-essential gcc git make flex bison \
+        software-properties-common libwww-perl python \
+        bin86 gdb bcc liblzma-dev python-dev gettext iasl \
+        uuid-dev libncurses5-dev libncursesw5-dev pkg-config \
+        libgtk2.0-dev libyajl-dev sudo time
+
+    - uses: actions/checkout@v1
+
+    - name: build CBMC tools
+      run: make -C src minisat2-download
+      run: make -C src cbmc.dir goto-cc.dir goto-diff.dir
+
+    - name: get Xen 4.13
+      run: git clone git://xenbits.xen.org/xen.git xen_4_13 && cd xen_4_13 && git reset --hard RELEASE-4.13.0