mtd: spi-nor: intel-spi: Add support for Intel Ice Lake SPI serial flash

Intel Ice Lake exposes the SPI serial flash controller as a PCI device
in the same way than Intel Denverton. Add Ice Lake SPI serial flash PCI
ID to the driver list of supported devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>