Add these ablkcipher algorithms:
cbc(aes),
cbc(des3_ede).

Added handling of chained scatterlists with zero length entry
because eseqiv uses it.
Added new map and unmap routines.
Signed-off-by: Lee Nipper <lee.nipper@gmail.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>