Add some missing function parameter typehints
Summary: Add some missing function parameter typehints to the ArcanistPhutilXHPASTLinter class.
Test Plan: Eyeball it.
Reviewers: epriestley, Blessed Reviewers
Reviewed By: epriestley, Blessed Reviewers
Subscribers: epriestley, Korvin
Differential Revision: https://secure.phabricator.com/D10430