[gnome-settings-daemon] color: Fix gsd-test-color linkage

[Bastien Nocera <hadess src gnome org>]

commit 818a6e99a51a18c01b50a661a641bd009136922d
Author: Bastien Nocera <hadess hadess net>
Date:   Wed Oct 5 14:29:54 2016 +0200

    color: Fix gsd-test-color linkage
    
    https://bugzilla.gnome.org/show_bug.cgi?id=741688#c66

 plugins/color/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/plugins/color/Makefile.am b/plugins/color/Makefile.am
index e38c288..3b56dd1 100644
--- a/plugins/color/Makefile.am
+++ b/plugins/color/Makefile.am
@@ -82,7 +82,7 @@ gsd_test_color_SOURCES =              \
 
 gsd_test_color_CFLAGS = $(libcolor_la_CFLAGS)
 gsd_test_color_CPPFLAGS = $(libcolor_la_CPPFLAGS)
-gsd_test_color_LDADD = $(libcolor_la_LIBADD) $(top_builddir)/gnome-settings-daemon/libgsd.la
+gsd_test_color_LDADD = $(libcolor_la_LIBADD) $(top_builddir)/gnome-settings-daemon/libgsd.la $(LIBM)
 
 plugin_in_files =                      \
        color.gnome-settings-plugin.in