[ARM] 3534/1: add spi support to lubbock platform

Patch from David Brownell

This adds the platform device for SSP/SPI controller, and declares
the ads7846 device hooked up to it.  Not all Lubbock boards appear
to populate the connector needed to use this instead of the ucb1400
chip, but it can always be used as a temperature sensor.

In short, this is probably most useful as an example of how to
provide the configuration data used by the pxa2xx_spi driver.
(Last tested against a slightly earlier version of that driver.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>