usb: mtu3: rebuild qmu_gpd struct to prepare to support new QMU format

To support USB3 Gen2 ISOC, the data buffer length need be extended,
it's hard to make the current qmu_gpd struct compatible, so here
rebuild qmu_gpd struct and make easy to support new QMU format

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>