libertas: make a handy lbs_cmd_async() command

This uses a static lbs_cmd_async_callback function, which is a
noop. Just setting the callback argument to __lbs_cmd_async()
to NULL won't work, because then the cmdnode wouldn't be
released.

This also makes __lbs_cmd_async() a static method, which is
now only used by lbs_cmd() and lbs_cmd_async().

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/libertas/cmd.h b/drivers/net/wireless/libertas/cmd.h
index d250e6b..3dfc2d4 100644
--- a/drivers/net/wireless/libertas/cmd.h
+++ b/drivers/net/wireless/libertas/cmd.h
@@ -18,12 +18,9 @@
 #define lbs_cmd_with_response(priv, cmdnr, cmd)	\
 	lbs_cmd(priv, cmdnr, cmd, lbs_cmd_copyback, (unsigned long) (cmd))
 
-/* __lbs_cmd() will free the cmdnode and return success/failure.
-   __lbs_cmd_async() requires that the callback free the cmdnode */
-struct cmd_ctrl_node *__lbs_cmd_async(struct lbs_private *priv, uint16_t command,
-				      struct cmd_header *in_cmd, int in_cmd_size,
-				      int (*callback)(struct lbs_private *, unsigned long, struct cmd_header *),
-				      unsigned long callback_arg);
+void lbs_cmd_async(struct lbs_private *priv, uint16_t command,
+	struct cmd_header *in_cmd, int in_cmd_size);
+
 int __lbs_cmd(struct lbs_private *priv, uint16_t command,
 	      struct cmd_header *in_cmd, int in_cmd_size,
 	      int (*callback)(struct lbs_private *, unsigned long, struct cmd_header *),