Don't complain about rules overlapping functions with no unfolding

This showed up when importing a module that was compiled
without -O, so there were no unfoldings in the interface file
Add debug dump of the list of Cmm proc points
Improve panic printout
When removing unreachable code, remove unreachable info tables too

This bug only shows up when you are using proc-point splitting.
What was happening was:
  * We generate a proc-point for the stack check
  * And an info table
  * We eliminate the stack check because it's redundant
  * And the dangling info table caused a panic in
    CmmBuildInfoTables.bundle