ASoC: stm32: sai: manage context in set_sysclk callback

ASoC: stm32: sai: manage context in set_sysclk callback

The mclk direction now needs to be specified in endpoint node with
"system-clock-direction-out" property. However some calls to the
set_sysclk callback, related to CPU DAI clock, result in unbalanced
calls to clock API.
The set_sysclk callback in STM32 SAI driver is intended only for mclk
management. So it is relevant to ensure that calls to set_sysclk are
related to mclk only.
Since the master clock is handled only at runtime, skip the calls to
set_sysclk in the initialization phase.

Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Link: https://patch.msgid.link/20250916123118.84175-1-olivier.moysan@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>