[llvm] [SPIRV] Add atan2 function lowering (p2) (PR #110037)

[Farzon Lotfi via llvm-commits]

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@@ -633,8 +633,8 @@ G_FCEIL, G_FSQRT, G_FFLOOR, G_FRINT, G_FNEARBYINT
 
 These correspond to the standard C functions of the same name.
 
-G_FCOS, G_FSIN, G_FTAN, G_FACOS, G_FASIN, G_FATAN, G_FCOSH, G_FSINH, G_FTANH
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+G_FCOS, G_FSIN, G_FTAN, G_FACOS, G_FASIN, G_FATAN, G_FCOSH, G_FSINH, G_FTANH, G_FATAN2
----------------
farzonl wrote:

maybe put G_FATAN2 with the other arc trig functions. 
```suggestion
G_FCOS, G_FSIN, G_FTAN, G_FACOS, G_FASIN, G_FATAN, G_FATAN2, G_FCOSH, G_FSINH, G_FTANH
```

https://github.com/llvm/llvm-project/pull/110037