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

[Zahira Ammarguellat via cfe-commits]

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@@ -360,6 +360,14 @@ Improvements to Clang's diagnostics
 
 - An error is now emitted when a ``musttail`` call is made to a function marked with the ``not_tail_called`` attribute. (#GH133509).
 
+- ``-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 (``/=``)
+
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zahiraam wrote:

NIT. Please put a "." at the end of each bullet.

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