spi: pxa2xx: Unify ifdeffery used in the headers

The two headers have quite different ifdeffery to prevent multiple inclusion.
Unify them with the pattern that in particular reflects their location.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210423182441.50272-6-andriy.shevchenko@linux.intel.com


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