spi: pxa2xx: Add support for Intel Alder Lake PCH-S

Add support for LPSS SPI on Intel Alder Lake. It has four LPSS SPI
controllers each having two chip selects.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20201204082409.183700-1-jarkko.nikula@linux.intel.com


Signed-off-by: Mark Brown <broonie@kernel.org>