Revert "Change Vec creation to check if gen is lit (and hence needs t… (#530)

* Revert "Change Vec creation to check if gen is lit (and hence needs to be declared)"

This reverts commit dc86e7e1734d6abacb739b488df1de231e6b41b2.
This may address #522 - using chiselCloneType (instead of cloneType) to preserve directionality.

* Add missing implicits to Vec.apply() signature.

* Use correct macro (CompileOptionsTransform) for indexWhere.