Haiku: Add missing EAI_SYSTEM const
Haiku: Add missing EAI_SYSTEM const

superriva/libc,cactorium/libc,zethra/libc,rust-lang-nursery/libc,superriva/libc,cactorium/libc,philippkeller/libc,mneumann/libc,anatol/libc,rust-lang/libc,mneumann/libc,zethra/libc,rust-lang-nursery/libc,philippkeller/libc,anatol/libc,superriva/libc,rust-lang-nursery/libc,anatol/libc,mneumann/libc,zethra/libc,rust-lang/libc,cactorium/libc,philippkeller/libc,rust-lang/libc