[cantarell-fonts] Introduce appdatadir variable

[Nikolaus Waxweiler <nwaxweiler src gnome org>]

commit acd5e5bd47093a8877fe268042e657d5a7a3ed18
Author: Nikolaus Waxweiler <madigens gmail com>
Date:   Wed Feb 7 20:52:42 2018 +0000

    Introduce appdatadir variable

 appstream/meson.build |    2 +-
 meson.build           |    1 +
 2 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/appstream/meson.build b/appstream/meson.build
index 15de1c0..4941521 100644
--- a/appstream/meson.build
+++ b/appstream/meson.build
@@ -5,5 +5,5 @@ appdata_file = i18n.merge_file(
   output: 'org.gnome.cantarell.metainfo.xml',
   po_dir: './',
   install: true,
-  install_dir: join_paths(get_option('datadir'), 'appdata'),
+  install_dir: appdatadir,
 )
diff --git a/meson.build b/meson.build
index 33c9985..d0a4ebd 100644
--- a/meson.build
+++ b/meson.build
@@ -1,6 +1,7 @@
 project('Cantarell', version : '0.100')
 
 datadir = join_paths(get_option('prefix'), get_option('datadir'))
+appdatadir = join_paths(datadir, 'appdata')
 
 fontsdir = get_option('fontsdir')
 if fontsdir == ''