Reason: similar change is present elsewhere in the code

Notes: please review carefully before accepting. patch propagation. manual test run. 
Reviewed By: https://github.com/dchichkov 
Cherry picked from:
===
From 0d62bd7 Mon Sep 17 00:00:00 2001
From: Juanjo Menent <jmenent@2byte.es>
Date: Wed, 22 Jun 2016 18:59:51 +0200
Subject: [PATCH] Fix: Bad column totalizing if MAIN_SHOW_HT_ON_SUMMARY activated

htdocs/compta/index.php

@@ -378,7 +378,7 @@
 				print '</tr>';
 
 				$total_ttc +=  $obj->total_ttc;
-				$total += $obj->total;
+				$total += $obj->total_hc;
 				$totalam +=  $obj->am;
 
 				$i++;