[gnome-system-monitor] help: Add missing figure to HELP_MEDIA

[Piotr Drąg <piotrdrag src gnome org>]

commit 2003a54b18cd36ea14f61d4165c4db3cce788754
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Sat Oct 21 20:39:27 2017 +0200

    help: Add missing figure to HELP_MEDIA
    
    It was forgotten in 03f2dafdc60d192269bfbd3a46ab20add0979c99,
    causing the icon to not be displayed in Yelp.

 help/Makefile.am |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/help/Makefile.am b/help/Makefile.am
index b8f6031..d90e248 100644
--- a/help/Makefile.am
+++ b/help/Makefile.am
@@ -29,7 +29,8 @@ HELP_FILES = \
        solaris-mode.page \
        units.page
 
-HELP_MEDIA =
+HELP_MEDIA = \
+       figures/monitorlogo.png
 
 HELP_LINGUAS = cs de el es fr hu ko pl pt pt_BR ro sv