unix: code for AIX ppc and ppc64, for gccgo

Change-Id: I187edceaf3604d73110940bd5580fa127a85e87d
Reviewed-on: https://go-review.googlesource.com/129735
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>

unix/syscall_aix_ppc.go

@@ -0,0 +1,34 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build aix
+// +build ppc
+
+package unix
+
+//sysnb	Getrlimit(resource int, rlim *Rlimit) (err error) = getrlimit64
+//sysnb	Setrlimit(resource int, rlim *Rlimit) (err error) = setrlimit64
+//sys	Seek(fd int, offset int64, whence int) (off int64, err error) = lseek64
+
+//sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
+
+func setTimespec(sec, nsec int64) Timespec {
+	return Timespec{Sec: int32(sec), Nsec: int32(nsec)}
+}
+
+func setTimeval(sec, usec int64) Timeval {
+	return Timeval{Sec: int32(sec), Usec: int32(usec)}
+}
+
+func (iov *Iovec) SetLen(length int) {
+	iov.Len = uint32(length)
+}
+
+func (msghdr *Msghdr) SetControllen(length int) {
+	msghdr.Controllen = uint32(length)
+}
+
+func (cmsg *Cmsghdr) SetLen(length int) {
+	cmsg.Len = uint32(length)
+}