Attempt to fix sysop paged emails not showing up

In issue 740, Keyop reported that emails with a body are not showing up in the iPhone email client. This just adds the subject to the body of the email. Tested and approved by Keyop.

src/sbbs3/chat.cpp

@@ -612,7 +612,7 @@ bool sbbs_t::sysop_page(void)
 		if(!(sys_status&SS_SYSPAGE)) {
 			logline("C", "paged sysop for chat");
 			SAFEPRINTF2(str, "%s paged you to chat from node %u", useron.alias, cfg.node_num);
-			notify(&cfg, 1, str, NULL);
+			notify(&cfg, 1, str, str);
 			ftouch(syspage_semfile);
 			char topic[128];
 			SAFEPRINTF(topic, "page/node/%u", cfg.node_num);