Add dbus signal for information about server certification

In general, this patch attemps to extend commit
00468b4650 with dbus support.

This can be used by dbus client to implement subject match text
entry with preset value probed from server. This preset value, if
user accepts it, is remembered and passed to subject_match config
for any future authentication.

Signed-off-by: Michael Chang <mchang@novell.com>

src/eap_peer/eap.c

@@ -1209,6 +1209,13 @@ static void eap_peer_sm_tls_event(void *ctx, enum tls_event ev,
 				     data->peer_cert.subject,
 				     cert_hex);
 		}
+		if (sm->eapol_cb->notify_cert) {
+			sm->eapol_cb->notify_cert(sm->eapol_ctx,
+						  data->peer_cert.depth,
+						  data->peer_cert.subject,
+						  hash_hex,
+						  data->peer_cert.cert);
+		}
 		break;
 	}