regulator: rpi-panel-attiny: 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 <liubo03@inspur.com>
Link: https://msgid.link/r/20240320085740.4604-14-liubo03@inspur.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Bo Liu

drivers/regulator/rpi-panel-attiny-regulator.c

@@ -75,7 +75,7 @@ static const struct regmap_config attiny_regmap_config = {
 	.val_bits = 8,
 	.disable_locking = 1,
 	.max_register = REG_WRITE_DATA_L,
-	.cache_type = REGCACHE_RBTREE,
+	.cache_type = REGCACHE_MAPLE,
 };
 
 static int attiny_set_port_state(struct attiny_lcd *state, int reg, u8 val)