gitlab-ci: Speed up the msys2-64bit job by using --without-default-devices

gitlab-ci: Speed up the msys2-64bit job by using --without-default-devices

The new msys2-64bit job is often running for more than 50 minutes - and
if the CI is currently loaded, it times out after 60 minutes. The job
has been declared with a bigger timeout, but seems like this is getting
ignored on the shared Gitlab-CI Windows runners, so we're currently
seeing a lot of failures with this job. Thus we have to reduce the time
it takes to finish this job. Since we want to test compiling the WHPX
and HAX accelerator code with this job, switching to another target CPU
is not really a good option, so let's reduce the amount of code that we
have to compile with the --without-default-devices switch instead.

Message-Id: <20211216082253.43899-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>