go.mod: update wireguard-go version.

I accidentally crushed one of crawshaw's patches, fixing this now.

go.mod

@@ -19,12 +19,12 @@ require (
 	github.com/peterbourgon/ff/v2 v2.0.0
 	github.com/tailscale/hujson v0.0.0-20190930033718-5098e564d9b3 // indirect
 	github.com/tailscale/winipcfg-go v0.0.0-20200213045944-185b07f8233f
-	github.com/tailscale/wireguard-go v0.0.0-20200301215411-6dde709dd694
+	github.com/tailscale/wireguard-go v0.0.0-20200301220325-351e6067e97c
 	golang.org/x/crypto v0.0.0-20200221231518-2aa609cf4a9d
 	golang.org/x/net v0.0.0-20200301022130-244492dfa37a // indirect
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
 	golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e
-	golang.org/x/sys v0.0.0-20200301040627-c5d0d7b4ec88
+	golang.org/x/sys v0.0.0-20200301204400-5d559ad92b82
 	golang.org/x/time v0.0.0-20191024005414-555d28b269f0
 	gortc.io/stun v1.22.1
 	honnef.co/go/tools v0.0.1-2019.2.3 // indirect

go.sum

@@ -162,6 +162,8 @@ golang.org/x/sys v0.0.0-20200217220822-9197077df867 h1:JoRuNIf+rpHl+VhScRQQvzbHe
 golang.org/x/sys v0.0.0-20200217220822-9197077df867/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200301040627-c5d0d7b4ec88 h1:LNVdAhESTW4gWDhYvciNcGoS9CEcxRiUKE9kSgw+X3s=
 golang.org/x/sys v0.0.0-20200301040627-c5d0d7b4ec88/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200301204400-5d559ad92b82 h1:lMQVwSjnOFtj3Ssuec21gK8stJac9xnIo2CjVk2cczw=
+golang.org/x/sys v0.0.0-20200301204400-5d559ad92b82/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=