[clang-tidy] Ignore macros defined within declarations

[clang-tidy] Ignore macros defined within declarations

Modernize-macro-to-enum shouldn't try to convert macros to enums
when they are defined inside a declaration or definition, only
when the macros are defined at the top level.  Since preprocessing
is disconnected from AST traversal, match nodes in the AST and then
invalidate source ranges spanning AST nodes before issuing diagnostics.

ClangTidyCheck::onEndOfTranslationUnit is called before
PPCallbacks::EndOfMainFile, so defer final diagnostics to the
PPCallbacks implementation.

Differential Revision: https://reviews.llvm.org/D124066

Fixes #54883