bug#58966: [Trunk] Xcode 14.1+ (and macOS 13.0+) deprecate sprintf()

[Stefan Kangas]

Richard Stallman <rms@gnu.org> writes:

> We could switch to snprintf, and define snprintf to call sprintf
> in systems where snprintf isn't available.

snprintf is part of the C99 standard, so I think we can always rely on
it being there.  Switching sounds like a good idea.