Rebecca Davis editorHong Kong “Mulan” star Donnie Yen this week reiterated his political loyalty to mainland China as he teased work on the upcoming theatrical adaptation of popular video game “Sleeping Dogs” and announced “Golden Empire,” a new China-backed crime thriller.His hometown is currently roiling under the impact of a controversial new national security law imposed by Beijing that strips Hong Kong of many of its former freedoms, which came into effect July 1 — the anniversary of