regmap: cache: Use BITS_TO_BYTES()

BITS_TO_BYTES() is the existing macro which takes care about full
bytes that may fully hold the given amount of bits. Use it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20241121105838.4073659-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: andy-shev

drivers/base/regmap/regcache.c

@@ -154,7 +154,7 @@ int regcache_init(struct regmap *map, const struct regmap_config *config)
 	map->num_reg_defaults = config->num_reg_defaults;
 	map->num_reg_defaults_raw = config->num_reg_defaults_raw;
 	map->reg_defaults_raw = config->reg_defaults_raw;
-	map->cache_word_size = DIV_ROUND_UP(config->val_bits, 8);
+	map->cache_word_size = BITS_TO_BYTES(config->val_bits);
 	map->cache_size_raw = map->cache_word_size * config->num_reg_defaults_raw;
 
 	map->cache = NULL;