[llvm] [test][MIPS] Remove unsafe-fp-math uses (NFC) (PR #164790)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-darwin` running on `doug-worker-3` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/23/builds/14972

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

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Driver/sigpipe-handling.c' FAILED ********************
Exit Code: 127

Command Output (stdout):
--
# RUN: at line 2
/Volumes/RAMDisk/buildbot-root/x86_64-darwin/build/bin/clang -E -fno-integrated-cc1 /Volumes/RAMDisk/buildbot-root/x86_64-darwin/llvm-project/clang/test/Driver/sigpipe-handling.c | head | /Volumes/RAMDisk/buildbot-root/x86_64-darwin/build/bin/FileCheck /Volumes/RAMDisk/buildbot-root/x86_64-darwin/llvm-project/clang/test/Driver/sigpipe-handling.c
# executed command: /Volumes/RAMDisk/buildbot-root/x86_64-darwin/build/bin/clang -E -fno-integrated-cc1 /Volumes/RAMDisk/buildbot-root/x86_64-darwin/llvm-project/clang/test/Driver/sigpipe-handling.c
# .---command stderr------------
# | Could not create process (/Volumes/RAMDisk/buildbot-root/x86_64-darwin/build/bin/clang) due to [Errno 24] Too many open files
# `-----------------------------
# error: command failed with exit status: 127

--

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


```

</details>

https://github.com/llvm/llvm-project/pull/164790