During V3Expand, some w32/1 (width == 32, widthMin == 1), nodes (e.g.:
RedOr) are replaced with w1 nodes (width == widthMin == 1) (e.g.: Neq).
However, V3Expand runs after V3Clean, when we are in C++ width world,
so we need to preserve the width/widthMin distinction, otherwise a later
constant folding can eliminate e.g. a necessary AstAnd used clear an
intermediate result (isAllOnes is true for a Const 1 with w1, but false
for a Const 1 with w32/1).
Attempting to fix by preserving all width/widthMin during a replacement
in V3Expand.
DFG itself is fine, but the transformed code hits the above.
Fixes#5953