ASoC: cs35l56: Waiting for firmware to boot must be tolerant of I/O errors

Ignore failure to read from the cs35l56 when polling as the device will
NAK i2c accesses until it has booted and this would terminate the poll
of regmap_read_poll_timeout().

Fixes: 8a731fd3

 ("ASoC: cs35l56: Move utility functions to shared file")
Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230829160433.2647889-1-rf@opensource.cirrus.com


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