ASoC: SOF: ipc4-control: Use local copy of IPC message for sending

ASoC: SOF: ipc4-control: Use local copy of IPC message for sending

If a kcontrol update comes to a control right at the same time when the
PCM containing the control is started up then there is a small window when
a race can happen:
while the widget is set up the swidget->setup_mutex is taken in topology
level and if the control update comes at this point, it will be stopped
within sof_ipc4_set_get_kcontrol_data() with the mutex and it will be
blocked until the swidget setup is done, which will clear the control's
IPC message payload.

To avoid such race, use local copy of the template IPC message instead of
the template directly. This will ensure data integrity in case of
concurrent updates during initialization.

Link: https://github.com/thesofproject/linux/issues/5734
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://patch.msgid.link/20260520141349.9625-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>