[llvm] [SCEV] Add predicated version of getSymbolicMaxBackedgeTakenCount. (PR #93498)

[Florian Hahn via llvm-commits]

fhahn wrote:

The PR contains 3 commits, 2 of which can be split off independently 1) refactoring getSymbolicMax to work on BackedgeTakenInfo directly and 2) adding tests for predicated symbolic max.

https://github.com/llvm/llvm-project/pull/93498