[clang] [lld] [llvm] [mlir] [NFC] Use more isa and isa_and_nonnull instead dyn_cast for predicates (PR #137393)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman approved this pull request.

Clang bits LGTM

https://github.com/llvm/llvm-project/pull/137393