Enable support of pm_runtime on STM32 SPDIFRX driver to allow
SPDIFRX power state monitoring.

Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Link: https://lore.kernel.org/r/20211119104752.13564-4-olivier.moysan@foss.st.com


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