[SCSI] bfa: DMA memory allocation enhancement.

- Modified the design such that each BFA sub-module will provide
  the amount of DMA and KVA memory needed by it and queues the
  same request to the global dma and kva info queues.
- During the memory allocation we iterate over this queue to allocate
  the dma and kva memory requested by sub-modules.
- The change is needed to avoid requesting the aggregate amount of memory
  needed by all the BFA sub-modules as one contiguous chunk.

Signed-off-by: Krishna Gudipati <kgudipat@brocade.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>