spi: dw-mid: remove Moorestown support

The support of the Moorestown was removed [1] from kernel long time ago. This
is just a follow up of that change.

[1] http://www.spinics.net/lists/platform-driver-x86/msg02948.html



Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>