regmap: pass buffer size to regmap_raw_read() in regcache_hw_init()

regcache_hw_init() uses regmap_raw_read() to initialize cache
when reg_defaults_raw isn't provided.

The last parameter to regmap_raw_read() is buffer size in bytes,
however regcache_hw_init() called it with number of registers
to read instead, which cause problem if they aren't one byte
wide in cache.

This wasn't triggered by any of current in-tree drivers
since they either have one-byte registers or provide
reg_defaults_raw explicitly.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/base/regmap/regcache.c

@@ -65,7 +65,7 @@ static int regcache_hw_init(struct regmap *map)
 			goto err_free;
 		}
 		ret = regmap_raw_read(map, 0, tmp_buf,
-				      map->num_reg_defaults_raw);
+				      map->cache_size_raw);
 		map->cache_bypass = cache_bypass;
 		if (ret < 0)
 			goto err_cache_free;