rapidio: add udev notification

Add RapidIO-specific modalias generation to enable udev notifications
about RapidIO-specific events.

The RapidIO modalias string format is shown below:

"rapidio:vNNNNdNNNNavNNNNadNNNN"

Where:
v  - Device Vendor ID (16 bit),
d  - Device ID (16 bit),
av - Assembly Vendor ID (16 bit),
ad - Assembly ID (16 bit),

as they are reported in corresponding Capability Registers (CARs)
of each RapidIO device.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@Prodrive.nl>
Cc: Micha Nelissen <micha.nelissen@Prodrive.nl>
Cc: Stef van Os <stef.van.os@Prodrive.nl>
Cc: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>