Maggie Smith, a star of stage and screen who became one of the most acclaimed actresses of our time, has died at age 89. In her long career, the British star won numerous awards, including an Oscar for her role in “The Prime of Miss Jean Brody.” But it was for her roles in “Harry Potter” as the acerbic dowager in “Downton Abbey” that many will remember her. NBC News’ Meghan Fitzgerald reports.