[clang] [libc] [Clang] Add width handling for <gpuintrin.h> shuffle helper (PR #125896)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-solaris11-sparcv9` running on `solaris11-sparcv9` while building `clang,libc` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/13/builds/5131

<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 'Clang :: Headers/gpuintrin.c' FAILED ********************
Exit Code: 2

Command Output (stderr):
--
RUN: at line 2: /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/bin/clang -cc1 -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/lib/clang/21/include -nostdsysteminc -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/Inputs/include    -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/../../lib/Headers/    -triple amdgcn-amd-amdhsa -emit-llvm /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c -o -  | /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/bin/FileCheck /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c --check-prefix=AMDGPU
+ /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/bin/clang -cc1 -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/lib/clang/21/include -nostdsysteminc -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/Inputs/include -internal-isystem /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/../../lib/Headers/ -triple amdgcn-amd-amdhsa -emit-llvm /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c -o -
+ /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/bin/FileCheck /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c --check-prefix=AMDGPU
/opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c:103:35: error: too few arguments to function call, expected 4, have 3
  103 |   __gpu_shuffle_idx_u32(-1, -1, -1);
      |   ~~~~~~~~~~~~~~~~~~~~~           ^
/opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/lib/clang/21/include/amdgpuintrin.h:148:1: note: '__gpu_shuffle_idx_u32' declared here
  148 | __gpu_shuffle_idx_u32(uint64_t __lane_mask, uint32_t __idx, uint32_t __x,
      | ^                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  149 |                       uint32_t __width) {
      |                       ~~~~~~~~~~~~~~~~
1 error generated.
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/stage1/bin/FileCheck /opt/llvm-buildbot/home/solaris11-sparcv9/clang-solaris11-sparcv9/llvm/clang/test/Headers/gpuintrin.c --check-prefix=AMDGPU

--

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


```

</details>

https://github.com/llvm/llvm-project/pull/125896