[ASTMatchers] Add support for dynamic matching of ofKind narrowing matcher

Summary: Adds support for using the ofKind in clang-query and other dynamic matcher use cases

Reviewers: klimek, aaron.ballman, jdoerfert

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77791