-simplifycfg is the legacy pass manager name for SimplifyCFGPass.
There is already a -simplify-cfg which handles options forin FUNCTION_PASS_WITH_PARAMS which
handles options for SimplifyCFGPass. Maybe that should be renamed to to
-simplifycfg as well?
This reduces the number of check-llvm failures under NewPM from 2619 to 2392.