crypto: iaa - Remove potential infinite loop in check_completion()

For iaa_crypto operations, it's assumed that if an operation doesn't
make progress, the IAA watchdog timer will kick in and set the
completion status bit to failure and the reason to completion timeout.

Some systems may have broken hardware that doesn't even do that, which
can result in an infinite status-checking loop. Add a check for that
in the loop, and disable the driver if it occurs.

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