[Bug target/113484] Add support for _Float16 type on PowerPC

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113484

--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Ah, this was about *actual* half-precision float, which indeed is 3.0 (Power9).

But all the same holds: it needs to be added to the ABI before we can have a
type for it, and it still won't be terribly useful (it will make for *slowe
code*, not using fewer resources either).