Remove reference map from another set of midend passes

[asl]

This includes less obvious cases. Plus some additional cleanup.

[asl]

Two issues were uncovered so far:

• DPDK backend has pass (DismantleMuxExpression) that relies on fresh refmap, but does not rebuild it. The code before PR is already problematic and worked by coincidence :)
• BMV2 PSA midend uses custom local copy propagation policy that relies on fresh external reference map (like "global variable"), so we really need to have refmap current there before local_copyprop.

Overall I think eventually we'd need passes to maintain their own copy of reference map if they really need it; we should not have global refmap object passed everywhere as maintaining its freshness is non-trivial and error-prone.