hw/audio/hda: fix memory leak on audio setup

hw/audio/hda: fix memory leak on audio setup

When SET_STREAM_FORMAT is called, the st->buft timer is overwritten, thus
causing a memory leak.  This was originally fixed in commit 816139ae6a5
("hw/audio/hda: fix memory leak on audio setup", 2024-11-14) but that
caused the audio to break in SPICE.

Fortunately, a simpler fix is possible.  The timer only needs to be
reset, because the callback is always the same (st->output is set at
realize time in hda_audio_init); call to timer_new_ns overkill.  Replace
it with timer_del and only initialize the timer once; for simplicity,
do it even if use_timer is false.

An even simpler fix would be to free the old time in hda_audio_setup().
However, it seems better to place the initialization of the timer close
to that of st->ouput.

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Message-ID: <20241114125318.1707590-3-pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
(cherry picked from commit 626b39006d2f9b1378a04cb88a2187bb852cb055)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>