We've had a few pull requests fixing format/argument mismatches
lately. I did't notice when PRINTF_F(format_index,first_arg_index)
attribute use and the checking gcc and clang do with it got removed,
but that was very useful. Putting it back triggers a whole bunch
of "format string is not literal" warnings, but that's because
'-Wformat-nonliteral' was explicitly added to the *.2020 hints.
Checking pline/You/&c arguments in the cases where the format is a
literal is more valuable than the complaints for sprintf being fed
a generated format, so reinstate PRINTF_F usage and turn off the
check for non-literal format strings.
5224d85ad3