unix: Fix *linkat on sparc64 and s390x

This fixes I8dc87401bb1025c2404e7304ecc4561edd67a452, which failed to
include the changes for s390x and sparc64, breaking the build for them.

Change-Id: I4899350580c36e4efbec9801345b5e32d624c849
Reviewed-on: https://go-review.googlesource.com/31185Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

unix/zsyscall_linux_s390x.go

@@ -64,7 +64,7 @@ func ppoll(fds *PollFd, nfds int, timeout *Timespec, sigmask *Sigset_t) (n int,
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
+func Readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
 	if err != nil {
@@ -87,7 +87,7 @@ func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
+func Symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(oldpath)
 	if err != nil {
@@ -109,7 +109,7 @@ func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func unlinkat(dirfd int, path string, flags int) (err error) {
+func Unlinkat(dirfd int, path string, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
 	if err != nil {

unix/zsyscall_linux_sparc64.go

@@ -64,7 +64,7 @@ func ppoll(fds *PollFd, nfds int, timeout *Timespec, sigmask *Sigset_t) (n int,
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
+func Readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
 	if err != nil {
@@ -87,7 +87,7 @@ func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
+func Symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(oldpath)
 	if err != nil {
@@ -109,7 +109,7 @@ func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func unlinkat(dirfd int, path string, flags int) (err error) {
+func Unlinkat(dirfd int, path string, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
 	if err != nil {