[Bug fortran/68009] [6/7 Regression] prototype for gfortran_runtime_error with inline matmul

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68009

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 6.2 is being released, adjusting target milestone.