fix expm1f overflow threshold

[quaternic]

Due to an erroneous overflow threshold, expm1f was incorrectly returning inf for inputs in the range [88.72169, 88.72283]. This additionally caused sinhf to return NaN for inputs in that range.

The bug was ported from the original in musl, which has since been fixed in
https://git.musl-libc.org/cgit/musl/commit/?id=964104f9f0e056cf58d9defa0b716d7756f040f6

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[quaternic]

CI failure seems unrelated to changes made:

error: linking with `link.exe` failed: exit code: 1120
  |
  = note: "C:\\Program Files\\Microsoft Visual Studio\\2022\\Enterprise\\VC\\Tools\\MSVC\\14.44.35207\\bin\\HostARM64\\arm64\\link.exe" "/NOLOGO" "<1 object files omitted>" "kernel32.lib" "msvcrt.lib" "C:\\a\\compiler-builtins\\compiler-builtins\\builtins-test-intrinsics\\target\\aarch64-pc-windows-msvc\\debug\\deps/libcompiler_builtins-18a27a1d28d46fb1.rlib" "/defaultlib:msvcrt" "/NXCOMPAT" "/OUT:C:\\a\\compiler-builtins\\compiler-builtins\\builtins-test-intrinsics\\target\\aarch64-pc-windows-msvc\\debug\\deps\\builtins_test_intrinsics.exe" "/OPT:REF,NOICF" "/DEBUG" "/PDBALTPATH:%_PDB%" "/NATVIS:<sysroot>\\lib\\rustlib\\etc\\intrinsic.natvis" "/NATVIS:<sysroot>\\lib\\rustlib\\etc\\liballoc.natvis" "/NATVIS:<sysroot>\\lib\\rustlib\\etc\\libcore.natvis" "/NATVIS:<sysroot>\\lib\\rustlib\\etc\\libstd.natvis"
  = note: some arguments are omitted. use `--verbose` to show all linker arguments
  = note: builtins_test_intrinsics.builtins_test_intrinsics.9c731a22e8747d26-cgu.0.rcgu.o : error LNK2019: unresolved external symbol __aarch64_cas16_relax referenced in function _RNvXs1q_NtNtCskIMISN2vbQ0_4core4sync6atomicNtB6_10AtomicI128NtNtBa_3fmt5Debug3fmt
          C:\a\compiler-builtins\compiler-builtins\builtins-test-intrinsics\target\aarch64-pc-windows-msvc\debug\deps\builtins_test_intrinsics.exe : fatal error LNK1120: 1 unresolved externals
          

@tgross35 Any idea what that is about?