JIT: Support delegate GDV guards in loop cloning (#75140)

JIT: Support delegate GDV guards in loop cloning (#75140)

Add support for cloning loops based on delegate GDV guards. Mark delegate address loads as invariant to allow VN and CSE of them.

Remove exceptions on indirs in guards after loop cloning, which otherwise prevents RBO from optimizing them away if the loop is inside an EH handler (e.g. foreach loop).