[clang] [llvm] [AMDGPU] Introduce GFX9/10.1/10.3/11 Generic Targets (PR #76955)

[Matt Arsenault via cfe-commits]

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@@ -520,6 +520,104 @@ Every processor supports every OS ABI (see :ref:`amdgpu-os`) with the following
 
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+Generic processors also exist.
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arsenm wrote:

Weird way to start this section 

https://github.com/llvm/llvm-project/pull/76955