ASoC: stm32: spdifrx: fix input pin state management

Changing input state in iec capture control is not safe,
as the pin state may be changed concurrently by ASoC
framework.
Remove pin state handling in iec capture control.

Note: This introduces a restriction on capture control,
when pin sleep state is defined in device tree. In this case
channel status can be captured only when an audio stream
capture is active.

Fixes: f68c2a68 ("ASoC: stm32: spdifrx: add power management")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Link: https://lore.kernel.org/r/20191204154333.7152-4-olivier.moysan@st.com


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