[3.14] gh-145801: Use gcc -fprofile-update=atomic for PGO builds (GH-145802) (#145892)

gh-145801: Use gcc -fprofile-update=atomic for PGO builds (GH-145802)

When Python build is optimized with GCC using PGO, use
-fprofile-update=atomic option to use atomic operations when updating
profile information. This option reduces the risk of gcov Data Files
(.gcda) corruption which can cause random GCC crashes.
(cherry picked from commit 08a018ebe0d673e9c352f790d2e4604d69604188)

Co-authored-by: Victor Stinner <vstinner@python.org>