rapidio: use Component Tag for unified switch identification

Change the way how switchid value is set.  Local counter variable does not
provide unified way to identify switch devices in a system with multiple
processors.  Using local counter leads to the situation when the same RIO
switch has different switch ID for each processor.  Replacing local
counter with unique portion of the Component Tag provides unified
reference to the switch by every processor in the system.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: 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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>