unix: add Ppoll on openbsd

Change-Id: I3a13730e219e6f6df28829cf0d1e193c62073ac8
Reviewed-on: https://go-review.googlesource.com/c/144057
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/unix/zsyscall_openbsd_arm.go b/unix/zsyscall_openbsd_arm.go
index 617d47f..0f7b4af 100644
--- a/unix/zsyscall_openbsd_arm.go
+++ b/unix/zsyscall_openbsd_arm.go
@@ -431,6 +431,17 @@
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func ppoll(fds *PollFd, nfds int, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {
+	r0, _, e1 := Syscall6(SYS_PPOLL, uintptr(unsafe.Pointer(fds)), uintptr(nfds), uintptr(unsafe.Pointer(timeout)), uintptr(unsafe.Pointer(sigmask)), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Access(path string, mode uint32) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)