[IPCOMP]: Fix false smp_processor_id warning

This patch fixes a false-positive from debug_smp_processor_id().

The processor ID is only used to look up crypto_tfm objects.
Any processor ID is acceptable here as long as it is one that is
iterated on by for_each_cpu().

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>