[clang] [clang] Fix-it hint for `++this` -> `++*this` when deref is modifiable (PR #94159)

[via cfe-commits]

Sirraide wrote:

> Checking for an overloaded operator* seems overly complicated here, so I think the right thing to test here is just whether the expression has pointer type, and the pointee type is an object type (not void or a function type).

That’s also what I was going for initially, but I thought that doing just that might lead to too many false positives... 

That said, considering all the issues that using `TentativeAnalysisScope` seems to come with, I suppose it’s not too surprising that it’s used very sparingly (most of the uses are apparently in Open MP–related code)

https://github.com/llvm/llvm-project/pull/94159