[libFuzzer] simplify the DFT trace collection using the new faster DFSan mode that traces up to 16 labels at a time and never runs out of labels. Second attempt. This time with a fix for windows (putenv instead of setenv))

llvm-svn: 363445
GitOrigin-RevId: 3f39123d15ba5e145ce81c63ea7e03c72c3b4f8f
3 files changed