ring-buffer: fix free page

The pages of a buffer was originally pointing to the page struct, it
now points to the page address. The freeing of the page still uses
the page frame free "__free_page" instead of the correct free_page to
the address.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/trace/ring_buffer.c

@@ -130,7 +130,7 @@ struct buffer_page {
 static inline void free_buffer_page(struct buffer_page *bpage)
 {
 	if (bpage->page)
-		__free_page(bpage->page);
+		free_page((unsigned long)bpage->page);
 	kfree(bpage);
 }