txstatus_timer should only be deleted for USB devices, as it is only
initialized for USB devices.
Reported-by: Andreas Hartmann <andihartmann@01019freenet.de> Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>