[clang] [llvm] [AMDGPU] Adding the amdgpu-num-work-groups function attribute (PR #79035)

[Jun Wang via cfe-commits]

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@@ -137,6 +137,12 @@ Removed Compiler Flags
 
 Attribute Changes in Clang
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+- Introduced a new function attribute ``__attribute__((amdgpu_max_num_work_groups(x, y, z)))`` or
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jwanggit86 wrote:

There are existing attributes that have workgroup spelled as two separate words: [flat-work-group-size](https://clang.llvm.org/docs/AttributeReference.html#amdgpu-flat-work-group-size), [reqd_work_group_size](https://docs.xilinx.com/r/2021.1-English/ug1393-vitis-application-acceleration/reqd_work_group_size).
Pls let me know if you still want workgroup as one word.

https://github.com/llvm/llvm-project/pull/79035