Out of what deal, exactly?
The digital merch and touring deal they inked in 2008 with LN? That has nothing to do with recording obligations. The only reason they'd need to "get out" of it would be if they wanted someone else to handle their digital merch and touring. If they tour never again (or once more and never again) they don't "owe" LN a tour.
And even this most recent deal has nothing to do with an obligation on the part of U2 to give LN n recordings by year whatever. As a matter of fact, it likely doesn't even drastically change whatever contract they have with Principle. It's not a recording contract between U2 and anyone. It's an ownership deal between PM and LN, to transfer control from PMcG to LN headed by GuyO.
U2 is affected, but it would appear only insofar as their assets being managed by new hands. Other artists in PM's stable will likewise experience the same change.
They can very well make this the last album and tour. Even this album and tour, they could pull the plug on and just pay out whoever they've already made promises to.
Now...would LN have paid $30M for an ownership deal of a company who's biggest client looks about to call it quits and not output anything ever again (other than reissues and compilations, of course)? Logically, no. But I don't think it necessarily means there's another decade or more of new U2 music, per se.