spi: pxa2xx: Replace of_device.h with mod_devicetable.h and of.h

There is nothing in use from of_device.h. The definitions and macros
are available thru mod_devicetable.h and of.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20191018105429.82782-5-andriy.shevchenko@linux.intel.com


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