No need to reinitialise the interrupt-in URB with values that have not
changed before (some) resubmissions.

This also allows the interrupt-in callback to have a single path for URB
resubmission.
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>