[Bug cobol/122398] [16 regression] libgcobol fails to build w/ libxml2-2.12.0

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122398

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
so simply make msg const I guess.