spi: pxa2xx: Remove unused psp member variable from struct chip_data
It is not used since commit 8d94cc50aa4f ("[PATCH] spi: stabilize PIO mode
transfers on PXA2xx systems").
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>