Log Message:
libffi: remove some netbsd/mips specific patches that are uneeded
(and may be harmful).

we don't need a definition to declare we're definitely totally o32,
especially since the vast majority will be n32. this is potentially
harmful, but I cannot confirm any resulting harm.

don't try to avoid compiler builtins, we have them and I expect that
they will work, however, only build tested (on netbsd 7.99.41 mips64eb),
no tests run.

bump PKGREVISION.