automation: add Ubuntu container for Xilinx hardware tests

This container is only run on the controller PC (x86) to trigger the
test on a connected Xilinx ZCU102 physical board.

Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>

automation/build/ubuntu/xenial-xilinx.dockerfile

@@ -0,0 +1,25 @@
+FROM ubuntu:16.04
+LABEL maintainer.name="The Xen Project " \
+      maintainer.email="xen-devel@lists.xenproject.org"
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV USER root
+
+RUN mkdir /build
+WORKDIR /build
+
+# board bringup depends
+RUN apt-get update && \
+    apt-get --quiet --yes install \
+        snmp \
+        snmp-mibs-downloader \
+        u-boot-tools \
+        device-tree-compiler \
+        cpio \
+        git \
+        gzip \
+        file \
+        && \
+        apt-get autoremove -y && \
+        apt-get clean && \
+        rm -rf /var/lib/apt/lists* /tmp/* /var/tmp/*