regulator: tps62360: enable register cache

Enable cache of device register using regmap cache RBTREE.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/tps62360-regulator.c

@@ -264,6 +264,8 @@ static int tps62360_init_dcdc(struct tps62360_chip *tps,
 static const struct regmap_config tps62360_regmap_config = {
 	.reg_bits		= 8,
 	.val_bits		= 8,
+	.max_register		= REG_CHIPID,
+	.cache_type		= REGCACHE_RBTREE,
 };
 
 static int __devinit tps62360_probe(struct i2c_client *client,