iio: light: ltr501: convert to use maple tree register cache

The maple tree register cache is based on a much more modern data structure
than the rbtree cache and makes optimisation choices which are probably
more appropriate for modern systems than those made by the rbtree cache.

Signed-off-by: chuguangqing <chuguangqing@inspur.com>
Link: https://patch.msgid.link/20250611085838.4761-10-chuguangqing@inspur.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/light/ltr501.c

@@ -1404,7 +1404,7 @@ static const struct regmap_config ltr501_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = LTR501_MAX_REG,
-	.cache_type = REGCACHE_RBTREE,
+	.cache_type = REGCACHE_MAPLE,
 	.volatile_reg = ltr501_is_volatile_reg,
 };