[clang] [analyzer] Fix FP for cplusplus.placement new #149240 (PR #150161)

[Donát Nagy via cfe-commits]

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@@ -179,8 +179,8 @@ void f2() {
 
   // maybe ok but we need to warn.
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NagyDonat wrote:

Similarly to the previous comment, explain that this testcase is a situation that _could_ be problematic, but the checker doesn't report it.

https://github.com/llvm/llvm-project/pull/150161