mfd: bd96801: Use maple tree register cache

The maple tree register cache uses a more modern data structure than the
rbtree cache and makes implementation decisions more suited to modern
hardware, switch the bd96801 driver to it to take advantage of this newer
code. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/20240924-mfd-bd96801-maple-v1-1-04fe33e1f009@kernel.org


Signed-off-by: Lee Jones <lee@kernel.org>