[minor] update pgp getPINNaïve so stty -echo is successful

See #316 for additional details

pgp/pinentry/pinentry.go

@@ -118,10 +118,12 @@ func (r *Request) GetPIN() (pin string, outerr error) {
 	return "", fmt.Errorf("GETPIN response didn't start with D; got %q", line)
 }
 
-func runPass(bin string, args ...string) {
+func runPass(bin string, args ...string) error {
 	cmd := exec.Command(bin, args...)
+	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
-	cmd.Run()
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
 }
 
 func (r *Request) getPINNaïve() (string, error) {
@@ -129,7 +131,10 @@ func (r *Request) getPINNaïve() (string, error) {
 	if err != nil {
 		return "", errors.New("no pinentry or stty found")
 	}
-	runPass(stty, "-echo")
+	err = runPass(stty, "-echo")
+	if err != nil {
+		return "", fmt.Errorf("error running stty: %v", err)
+	}
 	defer runPass(stty, "echo")
 
 	if r.Desc != "" {