[lib/Fuzzer] use -fsanitize-coverage=trace-cmp when building LLVM with LLVM_USE_SANITIZE_COVERAGE; in lib/Fuzzer try to reload the corpus to pick up new units from other processes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236906 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed