Any authorized Dealer , whether its BMW, Honda, Ducati etc. Will be able to do the firmware update. In fact its the first item they check when I'm booking the service even before they recieve the bike. Simply by using your VIN they check the service history. No different than any car service at a Dealership.
Sometimes the dealer won't update the firmware unless you report a problem that the newest update solves.
BMW R bikes take over an hour to update the TFT firmware and most dealers don't want to have the bike on the bench for that long. So a lot of folks are running older versions of the firmware even after the latest service.