regmap: Fix lock used for regcache_cache_only()

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 744ed145..4dfab41 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -273,9 +273,9 @@
  */
 void regcache_cache_only(struct regmap *map, bool enable)
 {
-	mutex_lock(&map->sync_lock);
+	mutex_lock(&map->lock);
 	map->cache_only = enable;
-	mutex_unlock(&map->sync_lock);
+	mutex_unlock(&map->lock);
 }
 EXPORT_SYMBOL_GPL(regcache_cache_only);