P2P: Add Group Info attr into Probe Response in GO without clients

While there is no real value in this, the spec seems to mark this
attribute as mandatory from GO, so better included it regardless
of whether we have clients or not (the attribute is empty in case
no clients are connected).

src/p2p/p2p_group.c

@@ -198,16 +198,14 @@ static struct wpabuf * p2p_group_build_probe_resp_ie(struct p2p_group *group)
 	/* P2P Device Info */
 	p2p_buf_add_device_info(ie, group->p2p, NULL);
 
-	if (group->members) {
-		/* P2P Group Info */
-		group_info = wpabuf_put(ie, 0);
-		wpabuf_put_u8(ie, P2P_ATTR_GROUP_INFO);
-		wpabuf_put_le16(ie, 0); /* Length to be filled */
-		for (m = group->members; m; m = m->next)
-			p2p_client_info(ie, m);
-		WPA_PUT_LE16(group_info + 1,
-			     (u8 *) wpabuf_put(ie, 0) - group_info - 3);
-	}
+	/* P2P Group Info */
+	group_info = wpabuf_put(ie, 0);
+	wpabuf_put_u8(ie, P2P_ATTR_GROUP_INFO);
+	wpabuf_put_le16(ie, 0); /* Length to be filled */
+	for (m = group->members; m; m = m->next)
+		p2p_client_info(ie, m);
+	WPA_PUT_LE16(group_info + 1,
+		     (u8 *) wpabuf_put(ie, 0) - group_info - 3);
 
 	p2p_buf_update_ie_hdr(ie, len);
 	return ie;