[Bug target/68822] Enable PowerPC divde instruction

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68822

--- Comment #2 from David Edelsohn <dje at gcc dot gnu.org> ---
Actually this needs support through divmodti4 pattern that falls back to
divmodtidi4 for DImode divisor.