[libFuzzer] add -print_final_stats=1 flag

llvm-svn: 262084
diff --git a/llvm/lib/Fuzzer/FuzzerFlags.def b/llvm/lib/Fuzzer/FuzzerFlags.def
index a451436..aed3e4e 100644
--- a/llvm/lib/Fuzzer/FuzzerFlags.def
+++ b/llvm/lib/Fuzzer/FuzzerFlags.def
@@ -74,4 +74,5 @@
                           "corpus, then merge with the initial corpus")
 FUZZER_FLAG_INT(output_csv, 0, "Enable pulse output in CSV format.")
 FUZZER_FLAG_INT(print_new_cov_pcs, 0, "If 1, print out new covered pcs.")
+FUZZER_FLAG_INT(print_final_stats, 0, "If 1, print statistics at exit.")