ASoC: cs42l73: Remove cache bypass for read of ID registers

Don't manually enable cache_bypass for reading the ID registers they
don't have a default anyway so the first read will always hit the
hardware. The old code worked this is simply the more standard way
to implement this.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Brian Austin <brian.austin@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>