[llvm] [AMDGPU] S_SET_GPR_IDX_ON can be passed an immediate index (PR #125086)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64le-linux-test-suite` running on `ppc64le-clang-test-suite` while building `llvm` at step 4 "cmake-configure".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/95/builds/9050

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

```
Step 4 (cmake-configure) failure: cmake (failure)
CMake Deprecation Warning at /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-test-suite/clang-ppc64le-test-suite/llvm-project/cmake/Modules/CMakePolicy.cmake:6 (cmake_policy):
  The OLD behavior for policy CMP0116 will be removed from a future version
  of CMake.

  The cmake-policies(7) manual explains that the OLD behaviors of all
  policies are deprecated and that a policy should be set to OLD only under
  specific short-term circumstances.  Projects should be ported to the NEW
  behavior and not rely on setting a policy to OLD.
Call Stack (most recent call first):
  CMakeLists.txt:8 (include)


CMake Error at CMakeLists.txt:47 (project):
  Running

   '/usr/bin/ninja-build' '--version'

  failed with:

   no such file or directory


-- Configuring incomplete, errors occurred!

```

</details>

https://github.com/llvm/llvm-project/pull/125086