[ARM] pxa: initial support for the Imote2 platform

Changes made as suggested by Eric Miao (including fix to map_io
silly mistake!).

Originally designed by Intel, now sold by Crossbow (www.xbow.com).

Very little actually on board. The patch includes sensors and
similar as found on commonly occurring daughter boards.

Some of the drivers are not in mainline as yet as they are either
part of the IIO subsystem or need a lot of work before submission.
What is the position wrt to putting them in i2c board configs etc?

Support for these boards has been maintained outside the kernel
for a long time, but now that there is a good da9030 pmic driver
available the last major hurdle no longer exists.

All comments welcomed.

The Imote2's big brother (stargate2) will follow once any problems
with this one have been cleaned up and a few bits and bobs have
been added to the da903x driver. Hopefully the cc2420 driver will
get cleaned up and submitted in the not too distant future as
well.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>