Update golang.org/x/sys commit hash to b4ddaad (#374)

Author: renovate[bot]

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/stretchr/testify v1.4.0 // indirect
 	golang.org/x/crypto v0.0.0-20190911031432-227b76d455e7 // indirect
 	golang.org/x/net v0.0.0-20190916140828-c8589233b77d // indirect
-	golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7 // indirect
+	golang.org/x/sys v0.0.0-20190916202348-b4ddaad3f8a3 // indirect
 	golang.org/x/text v0.3.2 // indirect
 	golang.org/x/tools v0.0.0-20190917032747-2dc213d980bc
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect

go.sum

@@ -71,6 +71,7 @@ golang.org/x/sys v0.0.0-20190909082730-f460065e899a/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190910064555-bbd175535a8b/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190911201528-7ad0cfa0b7b5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190916202348-b4ddaad3f8a3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=