bug#73068: printf: please implement POSIX:2024 argument reordering

[Bruno Haible]

Pádraig Brady wrote:
> I'll apply the attached sometime tomorrow.

Nice! Thank you.

There seems to be a typo in the unit test, though: It defines a shell
function 'printf_checki_err' but the function it then invokes is
'printf_check_err'.

Bruno