crypto: cavium/nitrox - NITROX command queue changes.

Use node based allocations for queues. consider the dma address
alignment changes, while calculating the queue base address.
added checks in cleanup functions. Minor changes to queue variable names

Signed-off-by: Srikanth Jampala <Jampala.Srikanth@cavium.com>
Reviewed-by: Gadam Sreerama <sgadam@cavium.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>