hmp: disable monitor in preconfig state

Ban it for now, if someone would need it to work early,
one would have to implement checks if HMP command is valid
at preconfig state.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1525423069-61903-5-git-send-email-imammedo@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

monitor.c

@@ -3371,6 +3371,12 @@ static void handle_hmp_command(Monitor *mon, const char *cmdline)
 
     trace_handle_hmp_command(mon, cmdline);
 
+    if (runstate_check(RUN_STATE_PRECONFIG)) {
+        monitor_printf(mon, "HMP not available in preconfig state, "
+                            "use QMP instead\n");
+        return;
+    }
+
     cmd = monitor_parse_command(mon, cmdline, &cmdline, mon->cmd_table);
     if (!cmd) {
         return;