lis3: SPI transport layer

Make use of the new abstraction layer and add a new transport layer for
spi.  Works fine on a PXA based board.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>