[llvm] [BOLT] Gadget scanner: detect non-protected indirect calls (PR #131899)

[Anatoly Trosinenko via llvm-commits]

atrosinenko wrote:

> That's actually fine as long as the GOT is RELRO, but I don't think this scanner could distinguish it.

I guess it should be possible to make BOLT understand this (by adding another register state: "non-signed, points to read-only memory"), but, of course, it would not work out-of-the-box.

https://github.com/llvm/llvm-project/pull/131899