crypto: talitos - ensure request ordering within a single tfm

Assign single target channel per tfm in talitos_cra_init instead of
performing channel scheduling dynamically during the encryption request.
This changes the talitos_submit interface to accept a new channel
number argument.  Without this, rapid bursts of misc. sized requests
could make it possible for IPsec packets to be encrypted out-of-order,
which would result in packet drops due to sequence numbers falling
outside the anti-reply window on a peer gateway.

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