coolrunner2: Add an ANDTERM/XOR between chained FFs
coolrunner2: Add an ANDTERM/XOR between chained FFs

In some cases (e.g. the low bits of counters) the design might end up
with a flip-flop whose input is directly driven by another flip-flop.
This isn't possible in the Coolrunner-II architecture, so add a single
AND term and XOR in this case.

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