Move interface data allocation to attach so that it is deallocated
should usb-serial probe fail.

Note that the usb device id is stored at probe so that it can be used
in attach to determine send-setup blacklisting.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>