USB: fix missing error check in probing

usb: check for IO errors usb_set_interface can return

if they happen while unbinding a flag is set to retry upon probe
if they happen during probe they are handled as probe errors

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>