At present the interrupt does not work and the SPI bus runs much less
quickly than it should. Add settings to fix this.
Signed-off-by: Simon Glass <sjg@chromium.org>
With the new device-tree rules it is possible to put device-tree changes
needed by U-Boot into their own file. As an example of this approach, move
Tegra over to use it.
Signed-off-by: Simon Glass <sjg@chromium.org>