In preparation for turning on opt's -enable-new-pm by default, this pins
uses of passes via the legacy "opt -passname" with pass names beginning
with "polly-" or "polyhedral-" to the legacy PM. Many of these tests use
-analyze, which isn't supported in the new PM.
(This doesn't affect uses of "opt -passes=passname").
The only pass with polyhedral- prefix is polyhedral-info, i.e. could be added to PassNameExact.