Rewrite the search cycle state machine to use a more data
oriented approach where the different Tx columns (configs)
limitations and next columns to search are reprsented in
tables which are easy to change. This overhaul also includes
several major fixes:

1. Prevent going back to a specific Tx column in a search
cycle if it was already explored.

2. Avoid switching to a Tx column that doesn't have any chance
if it performs perfectly to beat the current throughput we're
getting.

These issues were degrading throughput as they were causing
switching to "bad" Tx columns.
Signed-off-by: Eyal Shapira <eyal@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>