drivers/xen/xenbus/xenbus_client.c: cleanup kerneldoc

no argument named @xbt in xenbus_switch_state(), remove it.

Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 9678b3e..92a1ef8 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -136,7 +136,6 @@
 /**
  * xenbus_switch_state
  * @dev: xenbus device
- * @xbt: transaction handle
  * @state: new state
  *
  * Advertise in the store a change of the given driver to the given new_state.
@@ -267,7 +266,7 @@
  * @fmt: error message format
  *
  * Equivalent to xenbus_dev_error(dev, err, fmt, args), followed by
- * xenbus_switch_state(dev, NULL, XenbusStateClosing) to schedule an orderly
+ * xenbus_switch_state(dev, XenbusStateClosing) to schedule an orderly
  * closedown of this driver and its peer.
  */