[llvm] [AMDGPU][Verifier] Mark calls to entry functions as invalid in the IR verifier (PR #134910)

[Dmitry Sidorov via llvm-commits]

https://github.com/MrSidims commented:

This patch breaks tests for non AMDGPU code, see https://github.com/KhronosGroup/SPIRV-LLVM-Translator/actions/runs/14434681816/job/40473808013

>From OpenCL POW it's legal for a kernel to call another kernel.

https://github.com/llvm/llvm-project/pull/134910