rapidio: add outbound window support

Add RapidIO controller (mport) outbound window configuration operations.

This patch is a part of the original patch submitted by Li Yang:

   https://lists.ozlabs.org/pipermail/linuxppc-dev/2009-April/071210.html

For some reason the original part was not applied to mainline code
tree.  The inbound window mapping part has been applied later during
tsi721 mport driver submission.  Now goes the second part with
corresponding HW support.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>