When preparing for SG, not all the entries are prepared at once. When
resume, don't use the remaining request length to calculate for MPS
alignment. Use the entire request->length to do that.

Cc: stable@vger.kernel.org
Fixes: 5d187c04 ("usb: dwc3: gadget: Don't setup more than requested")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>