kfifo: fix a memory leak in dma example

We use a dynamically allocated kfifo in the dma example, so we need to
free it when unloading the module.

Signed-off-by: Andrea Righi <arighi@develer.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

samples/kfifo/dma-example.c

@@ -105,9 +105,7 @@ static int __init example_init(void)
 
 static void __exit example_exit(void)
 {
-#ifdef DYNAMIC
-	kfifo_free(&test);
-#endif
+	kfifo_free(&fifo);
 }
 
 module_init(example_init);