table: fix checking extended buckets in unoptimized case

table: fix checking extended buckets in unoptimized case

If a key is not found in a bucket and the bucket has been extended,
the extended buckets also have to checked for potentially matching
keys. The extended buckets are checked at the end of the lookup. In
most cases, this logic is skipped as it is uncommon to have buckets in
an extended state.

In case the lookup is performed with less than 5 packets, an
unoptimized version is run instead (the optimized version requires at
least 5 packets). The extended buckets should also be checked in this
case instead of simply ignoring the extended buckets.

Signed-off-by: Balazs Nemeth <balazs.nemeth@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>