I also filed a bug on this and got a reply stating that this is intentional. If you want to build for armv7s you have to add the architecture manually. I have now idea why this change was made. I’ll update this if I get additional information.
Update from the dev forums:
The reason for including armv7s would be marginal backward compatibility. But the general differences between armv7 and armv7s instruction sets are minor. So if you choose not to include armv7s, the targeted armv7 machine code still runs fine on 32 bit A6 devices, and hardly one will notice performance gap.
— Zhou Yang