go.mod: upgrade wireguard-windows, de-fork wireguard-go

Pull in the latest version of wireguard-windows.

Switch to upstream wireguard-go.
This requires reverting all of our import paths.

Unfortunately, this has to happen at the same time.
The wireguard-go change is very low risk,
as that commit matches our fork almost exactly.
(The only changes are import paths, CI files, and a go.mod entry.)
So if there are issues as a result of this commit,
the first place to look is wireguard-windows changes.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>

net/tstun/fake.go

@@ -8,7 +8,7 @@ import (
 	"io"
 	"os"
 
-	"github.com/tailscale/wireguard-go/tun"
+	"golang.zx2c4.com/wireguard/tun"
 )
 
 type fakeTUN struct {

net/tstun/ifstatus_noop.go

@@ -9,7 +9,7 @@ package tstun
 import (
 	"time"
 
-	"github.com/tailscale/wireguard-go/tun"
+	"golang.zx2c4.com/wireguard/tun"
 	"tailscale.com/types/logger"
 )
 

net/tstun/ifstatus_windows.go

@@ -9,7 +9,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/tailscale/wireguard-go/tun"
+	"golang.zx2c4.com/wireguard/tun"
 	"golang.zx2c4.com/wireguard/windows/tunnel/winipcfg"
 	"tailscale.com/types/logger"
 )

net/tstun/tun.go

@@ -13,7 +13,7 @@ import (
 	"runtime"
 	"time"
 
-	"github.com/tailscale/wireguard-go/tun"
+	"golang.zx2c4.com/wireguard/tun"
 	"tailscale.com/types/logger"
 	"tailscale.com/version/distro"
 )

net/tstun/tun_notwindows.go

@@ -6,7 +6,7 @@
 
 package tstun
 
-import "github.com/tailscale/wireguard-go/tun"
+import "golang.zx2c4.com/wireguard/tun"
 
 func interfaceName(dev tun.Device) (string, error) {
 	return dev.Name()

net/tstun/tun_windows.go

@@ -5,9 +5,9 @@
 package tstun
 
 import (
-	"github.com/tailscale/wireguard-go/tun"
-	"github.com/tailscale/wireguard-go/tun/wintun"
 	"golang.org/x/sys/windows"
+	"golang.zx2c4.com/wireguard/tun"
+	"golang.zx2c4.com/wireguard/tun/wintun"
 	"golang.zx2c4.com/wireguard/windows/tunnel/winipcfg"
 )
 

net/tstun/wrap.go

@@ -14,8 +14,8 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/tailscale/wireguard-go/device"
-	"github.com/tailscale/wireguard-go/tun"
+	"golang.zx2c4.com/wireguard/device"
+	"golang.zx2c4.com/wireguard/tun"
 	"inet.af/netaddr"
 	"tailscale.com/net/packet"
 	"tailscale.com/types/ipproto"

net/tstun/wrap_test.go

@@ -14,7 +14,7 @@ import (
 	"testing"
 	"unsafe"
 
-	"github.com/tailscale/wireguard-go/tun/tuntest"
+	"golang.zx2c4.com/wireguard/tun/tuntest"
 	"inet.af/netaddr"
 	"tailscale.com/net/packet"
 	"tailscale.com/types/ipproto"