[llvm] [AMDGPU] Move AMDGPUTargetMachine into AMDGPUCodeGenPassBuilder(NFC) (PR #103720)

[Christudasan Devadasan via llvm-commits]

cdevadas wrote:

* **#103721** <a href="https://app.graphite.dev/github/pr/llvm/llvm-project/103721?utm_source=stack-comment-icon" target="_blank"><img src="https://static.graphite.dev/graphite-32x32-black.png" alt="Graphite" width="10px" height="10px"/></a>
* **#103720** <a href="https://app.graphite.dev/github/pr/llvm/llvm-project/103720?utm_source=stack-comment-icon" target="_blank"><img src="https://static.graphite.dev/graphite-32x32-black.png" alt="Graphite" width="10px" height="10px"/></a> 👈
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https://github.com/llvm/llvm-project/pull/103720