pinctrl: sx150x: Use maple tree register cache

The sx150x driver uses a rbtree register cache with no obvious reason for
specifically preferring it. The maple tree register cache is based on a
more modern data structure and makes implementation decisions more suitable
for modern systems so let's switch the driver to use that. No functional
change.

Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/pinctrl/pinctrl-sx150x.c b/drivers/pinctrl/pinctrl-sx150x.c
index fd0331a..ab87de31 100644
--- a/drivers/pinctrl/pinctrl-sx150x.c
+++ b/drivers/pinctrl/pinctrl-sx150x.c
@@ -1105,7 +1105,7 @@ static const struct regmap_config sx150x_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 32,
 
-	.cache_type = REGCACHE_RBTREE,
+	.cache_type = REGCACHE_MAPLE,
 
 	.reg_read = sx150x_regmap_reg_read,
 	.reg_write = sx150x_regmap_reg_write,