usb: usbtmc: Fix suspend/resume

Submitted urbs are not allowed when system is suspended.
Thus the submitted urb waiting at interrupt pipe is killed
during suspend callback and submitted again when system resumes.

Signed-off-by: Guido Kiener <guido.kiener@rohde-schwarz.com>
Reviewed-by: Steve Bayless <steve_bayless@keysight.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>