[Bug c++/105626] -Wformat should accept u8"" strings

[drepper.fsp+rhbz at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105626

--- Comment #6 from Ulrich Drepper <drepper.fsp+rhbz at gmail dot com> ---
(In reply to Marek Polacek from comment #5)
> Fixed for GCC 13.  I could probably backport to GCC 12, if desirable.

Thanks.  And I certainly would appreciate a backport since this is an annoying
warning in some of my projects.