Recently we switched to using eseqiv on SMP machines in preference
over chainiv.  However, eseqiv does not support stream ciphers so
they should still default to chainiv.

This patch applies the same check as done by eseqiv to weed out
the stream ciphers.  In particular, all algorithms where the IV
size is not equal to the block size will now default to chainiv.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>