crypto: caam - chaining support

support chained scatterlists for aead, ablkcipher and ahash.

Signed-off-by: Yuan Kang <Yuan.Kang@freescale.com>

- fix dma unmap leak
- un-unlikely src == dst, due to experience with AF_ALG

Signed-off-by: Kudupudi Ugendreshwar <B38865@freescale.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>