regmap: Lock the sync path, ensure we use the lockless _regmap_write()

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index de32ced..40f23dd 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -327,7 +327,7 @@
 			if (val == def)
 				continue;
 			map->cache_bypass = 1;
-			ret = regmap_write(map, regtmp, val);
+			ret = _regmap_write(map, regtmp, val);
 			map->cache_bypass = 0;
 			if (ret)
 				return ret;