[ping] bug in __gmp_replacement_vsnprintf

[Paul Zimmermann]

       Hi,

this bug report from 3 years ago is still unanswered:

https://gmplib.org/list-archives/gmp-bugs/2022-October/005200.html

>From the last snapshot gmp-6.3.0-20241204172630, it seems %a/%A are
still not handled.

Please can you confirm this bug?

Paul