[llvm] [X86AsmBackend] Check fixup value overflow (PR #176827)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ppc64le-mlir-rhel-clang` running on `ppc64le-mlir-rhel-test` while building `llvm` at step 6 "test-build-check-mlir-build-only-check-mlir".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/129/builds/36971

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

```
Step 6 (test-build-check-mlir-build-only-check-mlir) failure: 1200 seconds without output running [b'ninja', b'check-mlir'], attempting to kill
...
PASS: MLIR :: mlir-runner/simple.mlir (3821 of 3832)
PASS: MLIR :: IR/parser.mlir (3822 of 3832)
PASS: MLIR :: mlir-tblgen/op-interface.td (3823 of 3832)
PASS: MLIR :: Transforms/test-operation-folder.mlir (3824 of 3832)
PASS: MLIR :: mlir-translate/split-markers.mlir (3825 of 3832)
PASS: MLIR :: Pass/ir-printing-file-tree.mlir (3826 of 3832)
PASS: MLIR :: mlir-runner/utils.mlir (3827 of 3832)
PASS: MLIR :: Pass/pipeline-options-parsing.mlir (3828 of 3832)
PASS: MLIR :: mlir-tblgen/op-error.td (3829 of 3832)
PASS: MLIR :: mlir-tblgen/llvm-intrinsics.td (3830 of 3832)
command timed out: 1200 seconds without output running [b'ninja', b'check-mlir'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1631.837838

```

</details>

https://github.com/llvm/llvm-project/pull/176827