[PGO] Enable InstrProf lowering for Clang PGO instrumentation in the new pass manager

Currently InstrProf lowering is not enabled for Clang PGO instrumentation in
the new pass manager. The following command
"-fprofile-instr-generate -fexperimental-new-pass-manager ..." is broken.

This CL enables InstrProf lowering pass for Clang PGO instrumentation in the
new pass manager.

Differential Revision: https://reviews.llvm.org/D61138

llvm-svn: 359215