Put your head down, do your job, and let it go. Get established at your employer, and if the coworker’s actions start affecting your work, then escalate. Any action now will not be beneficial. If you say something to the coworker, it’s not like they’re going to change their actions, and will more likely hold that against you, and likely talk to his peers. Talking to a manager will bring tattle tale / drama vibes and out you on radar.