usb: core: message: remove extra endianness conversion in usb_set_isoch_delay

No need to do extra endianness conversion in
usb_set_isoch_delay because it is already done
in usb_control_msg()

Fixes: 886ee36e ("usb: core: add support for USB_REQ_SET_ISOCH_DELAY")
Cc: Dmytro Panchenko <dmytro.panchenko@globallogic.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: stable <stable@vger.kernel.org> # v4.16+
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>