regmap: Cleanup and microoptimization

Merge series from Andy Shevchenko <andriy.shevchenko@linux.intel.com>:

Two patches move the code to use BITS_TO_BYTES(), while the last
one otpimizes the code generation on x86 (32- and 64-bit on different
compilers).

Author: broonie

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;

drivers/base/regmap/regmap.c

@@ -758,14 +758,13 @@ struct regmap *__regmap_init(struct device *dev,
 		map->alloc_flags = GFP_KERNEL;
 
 	map->reg_base = config->reg_base;
+	map->reg_shift = config->pad_bits % 8;
 
-	map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
 	map->format.pad_bytes = config->pad_bits / 8;
 	map->format.reg_shift = config->reg_shift;
-	map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
-	map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
-			config->val_bits + config->pad_bits, 8);
-	map->reg_shift = config->pad_bits % 8;
+	map->format.reg_bytes = BITS_TO_BYTES(config->reg_bits);
+	map->format.val_bytes = BITS_TO_BYTES(config->val_bits);
+	map->format.buf_size = BITS_TO_BYTES(config->reg_bits + config->val_bits + config->pad_bits);
 	if (config->reg_stride)
 		map->reg_stride = config->reg_stride;
 	else