[llvm] [SLP][AMDGPU] Fix load-address typo in v4f16 combine tests (PR #222112)

[Krzysztof Drewniak via llvm-commits]

https://github.com/krzysz00 approved this pull request.

Approved after the comment about the FIXME is addressed

https://github.com/llvm/llvm-project/pull/222112