Change default noc_biased_centroid_move weight

[vaughnbetz]

VTR can optimize placement of NoC routers and logic when a design contains both, but it doesn't have its best parameters set by default.

Expected Behaviour

The NoC biased centroid move should be on by default with the best weight (believed to be 0.2) if a design has NoC routers.

Current Behaviour

This move is off / weighted at 0 by default.

Possible Solution

Tune this parameter and set the best default.

Your Environment

VTR 9+ master