[clang] [Clang][Sema] Fix -Whigher-precision-for-complex-division (PR #131477)

[Zahira Ammarguellat via cfe-commits]

================
@@ -349,6 +349,17 @@ Improvements to Clang's diagnostics
 - Now correctly diagnose a tentative definition of an array with static
   storage duration in pedantic mode in C. (#GH50661)
 
+- ``-Whigher-precisision-for-complex-divison`` no longer incorrectly warns when the divisor is real
----------------
zahiraam wrote:

```suggestion
- ``-Whigher-precisision-for-complex-divison`` warns when:
•	The divisor is complex.
•	When the complex division happens in a higher precision type due to arithmetic promotion.
•	When using the divide and assign operator (/=).
```

https://github.com/llvm/llvm-project/pull/131477