usb: renesas_usbhs: add DMAEngine support

USB DMA was installed on "normal DMAC" when SH7724 or older SuperH,
but the "USB-DMAC" was prepared on recent SuperH.
These 2 DMAC have a little bit different behavior.

This patch add DMAEngine code for "normal DMAC",
but it is still using PIO fifo.
The DMA fifo will be formally supported in the future.

You can enable DMA fifo by local fixup
usbhs_fifo_pio_push_handler -> usbhs_fifo_dma_push_handler
usbhs_fifo_pio_pop_handler  -> usbhs_fifo_dma_pop_handler
on usbhsg_ep_enable.

This DMAEngine was tested by g_file_storage on SH7724 Ecovec board

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>