[Bug rtl-optimization/79856] rtl_verify_edges: use internal_error instead of error

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79856

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
So maybe we instead want a internal_error_cont () which will not end
compilation.