util/timer: avoid deadlock when shutting down

util/timer: avoid deadlock when shutting down

When we shut down a guest we disable the timers. However this can
cause deadlock if the guest has queued some async work that is trying
to advance system time and spins forever trying to wind time forward.
Pay attention to the return code and bail early if we can't wind time
forward.

Reported-by: Elisha Hollander <just4now666666@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240916085400.1046925-15-alex.bennee@linaro.org>
(cherry picked from commit bc02be4508d8753d1f6071b77d10f4661587df6f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>