tests/docker: Added docker build support for TSan.

Added a new docker for ubuntu 20.04.
This docker has support for Thread Sanitizer
including one patch we need in one of the header files.
a72dc86cd

This command will build with tsan enabled:
make docker-test-tsan-ubuntu2004 V=1

Also added the TSAN suppresion file to disable certain
cases of TSAN warnings.

Cc: Fam Zheng <fam@euphon.net>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Robert Foley <robert.foley@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200609200738.445-10-robert.foley@linaro.org>
Message-Id: <20200612190237.30436-13-alex.bennee@linaro.org>

tests/docker/dockerfiles/ubuntu2004.docker

@@ -0,0 +1,65 @@
+FROM ubuntu:20.04
+ENV PACKAGES flex bison \
+    ccache \
+    clang-10\
+    gcc \
+    gettext \
+    git \
+    glusterfs-common \
+    libaio-dev \
+    libattr1-dev \
+    libbrlapi-dev \
+    libbz2-dev \
+    libcacard-dev \
+    libcap-ng-dev \
+    libcurl4-gnutls-dev \
+    libdrm-dev \
+    libepoxy-dev \
+    libfdt-dev \
+    libgbm-dev \
+    libgtk-3-dev \
+    libibverbs-dev \
+    libiscsi-dev \
+    libjemalloc-dev \
+    libjpeg-turbo8-dev \
+    liblzo2-dev \
+    libncurses5-dev \
+    libncursesw5-dev \
+    libnfs-dev \
+    libnss3-dev \
+    libnuma-dev \
+    libpixman-1-dev \
+    librados-dev \
+    librbd-dev \
+    librdmacm-dev \
+    libsasl2-dev \
+    libsdl2-dev \
+    libseccomp-dev \
+    libsnappy-dev \
+    libspice-protocol-dev \
+    libspice-server-dev \
+    libssh-dev \
+    libusb-1.0-0-dev \
+    libusbredirhost-dev \
+    libvdeplug-dev \
+    libvte-2.91-dev \
+    libxen-dev \
+    libzstd-dev \
+    make \
+    python3-yaml \
+    python3-sphinx \
+    sparse \
+    texinfo \
+    xfslibs-dev\
+    vim
+RUN apt-get update && \
+    DEBIAN_FRONTEND=noninteractive apt-get -y install $PACKAGES
+RUN dpkg -l $PACKAGES | sort > /packages.txt
+ENV FEATURES clang tsan pyyaml sdl2
+
+# https://bugs.launchpad.net/qemu/+bug/1838763
+ENV QEMU_CONFIGURE_OPTS --disable-libssh
+
+# Apply patch https://reviews.llvm.org/D75820
+# This is required for TSan in clang-10 to compile with QEMU.
+RUN sed -i 's/^const/static const/g' /usr/lib/llvm-10/lib/clang/10.0.0/include/sanitizer/tsan_interface.h