NVIDIA's Tegra114 has 6 SPI controllers. These controllers are
redesign on T114 with different register interface.

Add DT entry for spi controllers and make it compatible with
"nvidia,tegra114-spi", since they are a new incompatible design.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
[swarren: fixed reg property for 3rd SPI controller]
Signed-off-by: Stephen Warren <swarren@nvidia.com>