[include-cleaner] Always treat constructor calls as implicit

Treating constructor calls when the type name isn't explicitly spelled
can cause spurious results, so turn them into implicit references.
This doesn't change the behaviour for constructor calls that explicitly spell
the type name, as we should see a reference through the typeloc.

Fixes https://github.com/llvm/llvm-project/issues/60812

Differential Revision: https://reviews.llvm.org/D144582