crypto: iaa - Remove header table code

The header table and related code is currently unused - it was
included and used for canned mode, but canned mode has been removed,
so this code can be safely removed as well.

This indirectly fixes a bug reported by Dan Carpenter.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-crypto/b2e0bd974981291e16882686a2b9b1db3986abe4.camel@linux.intel.com/T/#m4403253d6a4347a925fab4fc1cdb4ef7c095fb86


Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>