Intel® Arria® 10 SoC.
Cadence Quad SPI Flash is not generic SPI controller, but SPI flash
controller, so don't use spibus here, instead provide quad spi flash
interface.
Since it is not on spibus, then mx25l flash device driver is not usable
here, so provide new n25q flash device driver with quad spi flash
interface.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10245
