[Dominators] Change getNode parameter type to const NodeT * (NFC).

DominatorTreeBase::getNode does not modify its parameter and this change
allows callers that only have access to const pointers to use it without
casting.

Reviewers: kuhar, dblaikie, chandlerc

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D48231


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334892 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed