usb: chipidea: udc: Support SKB alignment quirk

NVIDIA Tegra20 UDC can't cope with unaligned DMA and require a USB gadget
quirk that avoids SKB buffer alignment to be set in order to make Ethernet
Gadget working. Later Tegra generations do not require that quirk. Let's
add a new platform data flag that allows to enable USB gadget quirk for
platforms that require it.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>