target/s390x: Expose s390_count_running_cpus() method

In order to simplify the next commit where s390_count_running_cpus()
is split out of s390_cpu_halt(), make its prototype public as a
preliminary step.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250708095746.12697-3-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2 files changed