P.F. Chang’s, one of the last remaining tenants at the nearly-empty White Flint Mall, may not be sticking around much longer. We hear the upscale Chinese restaurant could end up joining its former neighbor, Cheesecake Factory, in making the move to Westfield Montgomery Mall. Insiders say Montgomery wants to add more restaurants to the section where Cheesecake Factory moved last year, which so far includes Bobby’s Burger Palace, Aroma Espresso Bar and the soon-to-open Blaze Pizza. A furniture store in that area recently closed, and other departures are expected as the mall carves out space for more dining options. Even Old Navy is rumored to be on the way out — either leaving the mall altogether, or relocating to smaller quarters in another wing.