spi: add support for device table matching

spi: add support for device table matching

With this patch spi drivers can use standard spi_driver.id_table and
MODULE_DEVICE_TABLE() mechanisms to bind against the devices.  Just like
we do with I2C drivers.

This is useful when a single driver supports several variants of devices
but it is not possible to detect them in run-time (like non-JEDEC chips
probing in drivers/mtd/devices/m25p80.c), and when platform_data usage is
overkill.

This patch also makes life a lot easier on OpenFirmware platforms, since
with OF we extensively use proper device IDs in modaliases.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>