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

[Shilei Tian via cfe-commits]

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@@ -121,6 +121,7 @@ static const OffloadArchToStringMap arch_names[] = {
     GFX(909),  // gfx909
     GFX(90a),  // gfx90a
     GFX(90c),  // gfx90c
+    {OffloadArch::GFX9_4_GENERIC, "gfx9-4-generic", "compute_amdgcn"},
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shiltian wrote:

In fact, `gfx10-1-generic` was called `generic10.1-generic`, but that broke things like save temps, so all generic targets were renamed.

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