regmap: Do not call regcache_exit from regcache_lzo_init error path

Calling regcache_exit from regcache_lzo_init is first of all a layering
violation and secondly will cause double frees. regcache_exit will free buffers
allocated by the core, but the core will also free the same buffers when the
cacheops init callback returns an error. Thus we end up with a double free.
Fix this by not calling regcache_exit but only free those buffers which, have
been allocated in this function.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/base/regmap/regcache-lzo.c

@@ -15,6 +15,8 @@
 
 #include "internal.h"
 
+static int regcache_lzo_exit(struct regmap *map);
+
 struct regcache_lzo_ctx {
 	void *wmem;
 	void *dst;
@@ -193,7 +195,7 @@ static int regcache_lzo_init(struct regmap *map)
 
 	return 0;
 err:
-	regcache_exit(map);
+	regcache_lzo_exit(map);
 	return ret;
 }