ARM: pxa: ssp: Fix build error by removing originally incorrect DT binding

Commit 03fbf488 ("spi: pxa2xx: Differentiate Intel LPSS types") caused
build error here because it removed the type LPSS_SSP and I didn't notice
the type was used here too.

I believe commit a6e56c28 ("ARM: pxa: ssp: add DT bindings") added it
accidentally by copying all enum pxa_ssp_type types from
include/linux/pxa2xx_ssp.h even LPSS_SSP was for Intel LPSS SPI devices.

Fix the build error by removing this incorrect binding.

Fixes: 03fbf488

 ("spi: pxa2xx: Differentiate Intel LPSS types")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reported-by: Axel Lin <axel.lin@ingics.com>
Cc: <stable@vger.kernel.org> # 4.2
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>