ASoC: fsl_spdif: add ALSA event on dpll locked

Add an ALSA event on the RX Sample Rate controller upon the dpll locked
interrupt, making it possible for audio applications to monitor changes
in the hardware.

Signed-off-by: Robert Rosengren <robert.rosengren@axis.com>
Acked-by: Shengjiu Wang <shengjiu.wang@gmail.com>
Link: https://lore.kernel.org/r/20220912105407.3157868-1-robert.rosengren@axis.com


Signed-off-by: Mark Brown <broonie@kernel.org>