USB: otg: add otg_put_transceiver()

As Russell King points out, calling put_device(otg_transceiver->dev)
directly in driver cleanup paths makes assumptions about otg_transceiver
internals.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
index 1db25d1..94df4fe 100644
--- a/include/linux/usb/otg.h
+++ b/include/linux/usb/otg.h
@@ -84,6 +84,7 @@
 
 /* for usb host and peripheral controller drivers */
 extern struct otg_transceiver *otg_get_transceiver(void);
+extern void otg_put_transceiver(struct otg_transceiver *);
 
 static inline int
 otg_start_hnp(struct otg_transceiver *otg)