ASoC: cs4271: flat regcache, trivial simplifications

- Switch to REGCACHE_FLAT, the whole overhead of RBTREE is not worth it
with non sparse register set in the address range 1..7.
- Move register width to central location

Signed-off-by: Alexander Sverdlin <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/cs4271-i2c.c

···
 
 	config = cs4271_regmap_config;
 	config.reg_bits = 8;
-	config.val_bits = 8;
 
 	return cs4271_probe(&client->dev,
 			    devm_regmap_init_i2c(client, &config));

sound/soc/codecs/cs4271-spi.c

···
 
 	config = cs4271_regmap_config;
 	config.reg_bits = 16;
-	config.val_bits = 8;
 	config.read_flag_mask = 0x21;
 	config.write_flag_mask = 0x20;
 

sound/soc/codecs/cs4271.c

···
 
 	.reg_defaults = cs4271_reg_defaults,
 	.num_reg_defaults = ARRAY_SIZE(cs4271_reg_defaults),
-	.cache_type = REGCACHE_RBTREE,
-
+	.cache_type = REGCACHE_FLAT,
+	.val_bits = 8,
 	.volatile_reg = cs4271_volatile_reg,
 };
 EXPORT_SYMBOL_GPL(cs4271_regmap_config);