os/exec: gofmt

CL 109361 introduced some changes which were not properly gofmt'ed.
Because the CL was sent via Github no gofmt checks were performed
on it (cf. #24946, #18548).

Change-Id: I207065f01161044c420e272f4fd112e0a59be259
Reviewed-on: https://go-review.googlesource.com/115356
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/os/exec/lp_windows_test.go

@@ -117,7 +117,7 @@ func createEnv(dir, PATH, PATHEXT string) []string {
 		dirs[i] = filepath.Join(dir, dirs[i])
 	}
 	path := strings.Join(dirs, ";")
-	env = updateEnv(env, "PATH", os.Getenv("SystemRoot") + "/System32;" + path)
+	env = updateEnv(env, "PATH", os.Getenv("SystemRoot")+"/System32;"+path)
 	return env
 }