[libFuzzer] Fix incorrect coverage number in fork mode (#82335)
Closes #82307.
I built LLVM with the changes and tested fuzzing in fork mode. The
coverage number was correct:
```
[ye@ye-arch ~]$ /home/ye/work/llvm-project/build/bin/clang++ -fsanitize=fuzzer test_fuzzer.cc
[ye@ye-arch ~]$ ./a.out corpus -fork=4
INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 3152497917
INFO: Loaded 1 modules (40 inline 8-bit counters): 40 [0x5aa6f7b310d0, 0x5aa6f7b310f8),
INFO: Loaded 1 PC tables (40 PCs): 40 [0x5aa6f7b310f8,0x5aa6f7b31378),
INFO: -fork=4: fuzzing in separate process(s)
INFO: -fork=4: 56 seed inputs, starting to fuzz in /tmp/libFuzzerTemp.FuzzWithFork54465.dir
#600649: cov: 36 ft: 224 corp: 56 exec/s: 300324 oom/timeout/crash: 0/0/0 time: 2s job: 1 dft_time: 0
#1548208: cov: 36 ft: 224 corp: 56 exec/s: 315853 oom/timeout/crash: 0/0/0 time: 3s job: 2 dft_time: 0
#2465991: cov: 36 ft: 224 corp: 56 exec/s: 229445 oom/timeout/crash: 0/0/0 time: 4s job: 3 dft_time: 0
#3887877: cov: 36 ft: 224 corp: 56 exec/s: 284377 oom/timeout/crash: 0/0/0 time: 5s job: 4 dft_time: 0
```
NOKEYCHECK=True
GitOrigin-RevId: 83251a22f623df8d27b6184d19b24c18d314f2bd
1 file changed
