Previously used “unsigned long” may lead to confusion should the code
be compiled for 64-bit machine.
This commit also removes some unused fields of the tegra_spi_data
structure as well as removes duplicated #defines.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Tested-by: Stephen Warren <swarren@nvidia.com> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@linaro.org>