[shotwell] build: use APPSTREAM_XML instead of APPDATA_XML

[Jens Georg <jensgeorg src gnome org>]

commit ca81bf374902c9a07e695d8cab97a2bfd45ea235
Author: Brian Masney <masneyb onstation org>
Date:   Wed Jul 12 19:29:12 2017 -0400

    build: use APPSTREAM_XML instead of APPDATA_XML
    
    According to commit 8c0c9ec747bc in the appstream-glib project
    (https://github.com/hughsie/appstream-glib), APPDATA_XML has been
    deprecated and APPSTREAM_XML should be used insted. Fedora 26
    no longer ships with appdata-xml.m4 in the libappstream-glib-devel
    package. This patch converts the build system to use APPSTREAM_XML.
    
    Signed-off-by: Brian Masney <masneyb onstation org>
    
    https://bugzilla.gnome.org/show_bug.cgi?id=784883

 configure.ac     |    4 ++--
 misc/Makefile.am |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 2ed72cb..ec5846b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -267,8 +267,8 @@ YELP_HELP_INIT
 dnl ***********************************************************************
 dnl AppData support
 dnl ***********************************************************************
-AX_REQUIRE_DEFINED([APPDATA_XML])
-APPDATA_XML
+AX_REQUIRE_DEFINED([APPSTREAM_XML])
+APPSTREAM_XML
 
 dnl ***********************************************************************
 dnl GResource compiler
diff --git a/misc/Makefile.am b/misc/Makefile.am
index 3ccf48b..77729da 100644
--- a/misc/Makefile.am
+++ b/misc/Makefile.am
@@ -16,7 +16,7 @@ $(appdata_XML) : $(appdata_in_files)
        $(AM_V_GEN) $(MSGFMT) --desktop --template $< -d $(top_srcdir)/po -o $@
 
 @GSETTINGS_RULES@
-@APPDATA_XML_RULES@
+@APPSTREAM_XML_RULES@
 
 CLEANFILES = $(appdata_XML) $(desktop_DATA) $(desktop_in_files)