Callum Keith Rennie (“Tin Man” ) and Adam Godley (“Around the World in 80 Days”) have signed on to co-star in the untitled “X-Files” sequel for 20th Century Fox. Rennie’s credits include “Men in Trees” and the upcoming “Case 39,” opposite Renee Zellweger. Godley’s credits include “Charlie and the Chocolate Factory” and “Elizabeth: The Golden Age.”