ASoC: SDCA: mask Function_Status value

ASoC: SDCA: mask Function_Status value

According to the SDCA specification [1], when writing Function_Status during
handling this control, the value should mask off bit 7.

[1] MIPI Specification for SoundWire Device Class for Audio, version
    1.1, section 7.14.1.3 (Host Software Handling of Function_Status)

Signed-off-by: Maciej Strozek <mstrozek@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20260408093835.2881486-3-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>