RapidIO: Tsi721 driver - fixes for the initial release

RapidIO: Tsi721 driver - fixes for the initial release

- address comments made by Andrew Morton,
  see http://marc.info/?l=linux-kernel&m=131361256714116&w=2
- add spinlock for IB_MSG handler
- rename private BDMA channel structure to avoid conflict with DMA engine
- fix endianess bug in outbound message interrupt handler

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Chul Kim <chul.kim@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>