bpo-35499: make profile-opt don't override CFLAGS_NODIST (GH-11164) (GH-11179)

"make profile-opt" no longer replaces CFLAGS_NODIST with CFLAGS. It
now adds profile-guided optimization (PGO) flags to CFLAGS_NODIST,
existing CFLAGS_NODIST flags are kept.
(cherry picked from commit 640ed520dd6a43a8bf470b79542f58b5d57af9de)

Co-authored-by: Victor Stinner <vstinner@redhat.com>
2 files changed