Hi @diresu. Welcome to GoDaddy Community! From what I can see using browser network tools, our Linux servers already support HTTP/2. If you're seeing evidence that this isn't the case, you may want to connect with our hosting support team to have your account reviewed.
I would also like to know how to enable HTTP/2 on GoDaddy cPanel... Googles light-House audit of my web site is showing HTTP/1.
I just spoke (11/7/17) with web hosting support and they inform me http/2 is only supported on their Wordpress platform. None of the techs knew of any plan to support http/2 on deluxe linux or any other hosting options. Hope GoDaddy addresses this soon so I don't have to move myself plus all my clients over to another provider.