mfd: rn5t618: 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: Bo Liu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lee Jones <[email protected]>

drivers/mfd/rn5t618.c

@@ -62,7 +62,7 @@ static const struct regmap_config rn5t618_regmap_config = {
 	.val_bits	= 8,
 	.volatile_reg	= rn5t618_volatile_reg,
 	.max_register	= RN5T618_MAX_REG,
-	.cache_type	= REGCACHE_RBTREE,
+	.cache_type	= REGCACHE_MAPLE,
 };
 
 static const struct regmap_irq rc5t619_irqs[] = {