scripts/run-coverity-scan: Script to run Coverity Scan build

scripts/run-coverity-scan: Script to run Coverity Scan build

Add a new script to automate the process of running the Coverity
Scan build tools and uploading the resulting tarball to the
website.

This is intended eventually to be driven from Travis,
but it can be run locally, if you are a maintainer of the
QEMU project on the Coverity Scan website and have the secret
upload token.

The script must be run on a Fedora 30 system.  Support for using a
Docker container is added in a following commit.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200319193323.2038-6-peter.maydell@linaro.org