rapidio: modify configuration to support PCI-SRIO controller

1. Add an option to include RapidIO support if the PCI is available.
2. Add FSL_RIO configuration option to enable controller selection.
3. Add RapidIO support option into x86 and MIPS architectures.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.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>