[compiler-rt] Revert "[libfuzzer] use timer_create() instead of setitimer() for linux" (PR #115811)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-s390x-linux` running on `systemz-1` while building `compiler-rt` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/42/builds/1861

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'SanitizerCommon-tsan-s390x-Linux :: Linux/getpwnam_r_invalid_user.cpp' FAILED ********************
Exit Code: 134

Command Output (stderr):
--
RUN: at line 2: /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/./bin/clang  --driver-mode=g++ -gline-tables-only -fsanitize=thread  -funwind-tables  -I/home/uweigand/sandbox/buildbot/clang-s390x-linux/llvm/compiler-rt/test -ldl -O0 -g /home/uweigand/sandbox/buildbot/clang-s390x-linux/llvm/compiler-rt/test/sanitizer_common/TestCases/Linux/getpwnam_r_invalid_user.cpp -o /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.tmp &&  /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.tmp
+ /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/./bin/clang --driver-mode=g++ -gline-tables-only -fsanitize=thread -funwind-tables -I/home/uweigand/sandbox/buildbot/clang-s390x-linux/llvm/compiler-rt/test -ldl -O0 -g /home/uweigand/sandbox/buildbot/clang-s390x-linux/llvm/compiler-rt/test/sanitizer_common/TestCases/Linux/getpwnam_r_invalid_user.cpp -o /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.tmp
+ /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.tmp
getpwnam_r_invalid_user.cpp.tmp: /home/uweigand/sandbox/buildbot/clang-s390x-linux/llvm/compiler-rt/test/sanitizer_common/TestCases/Linux/getpwnam_r_invalid_user.cpp:17: int main(): Assertion `res == 0 || res == ENOENT' failed.
/home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.script: line 1: 3254217 Aborted                 /home/uweigand/sandbox/buildbot/clang-s390x-linux/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/tsan-s390x-Linux/Linux/Output/getpwnam_r_invalid_user.cpp.tmp

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/115811