[clang] [llvm] [AMDGPU] Introduce a new generic target `gfx9-4-generic` (PR #115190)

[Konstantin Zhuravlyov via cfe-commits]

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@@ -576,6 +576,12 @@ Generic processor code objects are versioned. See :ref:`amdgpu-generic-processor
                                                                                                   - ``v_dot2_f32_f16``
 
 
+     ``gfx9-4-generic``   ``amdgcn``     - ``gfx940``      - xnack            - Absolute flat   FP8 and BF8 instructions,
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kzhuravl wrote:

so should be added to target features supported column?

https://github.com/llvm/llvm-project/pull/115190