V4L/DVB (5507): Pvrusb2: Gather USB bus address info and report it

The V4L2 API requires a unique bus_info string returned as part of the
v4l2_capability structure.  These changes gather up the USB address
information, from the underlying device, into a string and report that
out through v4l2 and via sysfs (for completeness).

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw.h b/drivers/media/video/pvrusb2/pvrusb2-hdw.h
index 0c9cca4..4dba8d0 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-hdw.h
+++ b/drivers/media/video/pvrusb2/pvrusb2-hdw.h
@@ -124,6 +124,9 @@
 /* Retrieve serial number of device */
 unsigned long pvr2_hdw_get_sn(struct pvr2_hdw *);
 
+/* Retrieve bus location info of device */
+const char *pvr2_hdw_get_bus_info(struct pvr2_hdw *);
+
 /* Called when hardware has been unplugged */
 void pvr2_hdw_disconnect(struct pvr2_hdw *);