regmap: Initialize `map->debugfs' before regcache

In the rbtree code we are exposing statistics relating to the
number of nodes/registers of the rbtree cache for each of the
devices.  Ensure that `map->debugfs' has been initialized before
we attempt to initialize the debugfs entry for the rbtree cache.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org

drivers/base/regmap/regmap.c

@@ -710,12 +710,12 @@ struct regmap *regmap_init(struct device *dev,
 		}
 	}
 
+	regmap_debugfs_init(map, config->name);
+
 	ret = regcache_init(map, config);
 	if (ret != 0)
 		goto err_range;
 
-	regmap_debugfs_init(map, config->name);
-
 	/* Add a devres resource for dev_get_regmap() */
 	m = devres_alloc(dev_get_regmap_release, sizeof(*m), GFP_KERNEL);
 	if (!m) {