[easytag] Only install the metainfo file if requested

[David King <davidk src gnome org>]

commit 30e2c672106ec5177f421cc577214bc562610517
Author: David King <amigadave amigadave com>
Date:   Sun Feb 14 09:40:07 2016 +0000

    Only install the metainfo file if requested
    
    Only install the AppData metainfo file for the Nautilus extension if the
    extension is enabled.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=761996

 Makefile.am |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index f76ba68..d791604 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -268,6 +268,8 @@ libnautilus_easytag_la_LDFLAGS = \
 
 libnautilus_easytag_la_LIBADD = \
        $(NAUTILUS_LIBS)
+
+nautilus_appdata_in_file = data/easytag-nautilus.metainfo.xml.in
 endif
 
 # Create a directory stamp in the build dir. Used to workaround the case where
@@ -279,7 +281,7 @@ endif
 
 @APPDATA_XML_RULES@
 @INTLTOOL_XML_RULE@
-appdata_in_files = data/easytag.appdata.xml.in data/easytag-nautilus.metainfo.xml.in
+appdata_in_files = data/easytag.appdata.xml.in $(nautilus_appdata_in_file)
 appdata_XML = $(appdata_in_files:.xml.in=.xml)
 
 @INTLTOOL_DESKTOP_RULE@