[Bug tree-optimization/123113] factor_out_conditional_operation could be improved to handle `EDGE_COUNT (merge->preds) != 2`

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123113

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So thinking about how to handle this is we need to create a new merge block for
where the expressions should go. Basically kinda of undo merge phi but slightly
different.