pipe: fix comment in pipe_buf_operations

Map and unmap ops no longer exist.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index bddccf0..e7497c9 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -66,15 +66,10 @@
  *
  * ->confirm()
  *	->steal()
- *	...
- *	->map()
- *	...
- *	->unmap()
  *
- * That is, ->map() must be called on a confirmed buffer,
- * same goes for ->steal(). See below for the meaning of each
- * operation. Also see kerneldoc in fs/pipe.c for the pipe
- * and generic variants of these hooks.
+ * That is, ->steal() must be called on a confirmed buffer.
+ * See below for the meaning of each operation. Also see kerneldoc
+ * in fs/pipe.c for the pipe and generic variants of these hooks.
  */
 struct pipe_buf_operations {
 	/*