[gedit] build: avoid the use of a global variable

[Sébastien Wilmet <swilmet src gnome org>]

commit bffe6c570d9f9df4d6449f1397370452c7d2ed9f
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Wed Dec 4 17:01:22 2019 +0100

    build: avoid the use of a global variable
    
    In this case, datadir.

 data/meson.build | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)
---
diff --git a/data/meson.build b/data/meson.build
index 2261d028a..2379b78cc 100644
--- a/data/meson.build
+++ b/data/meson.build
@@ -1,9 +1,19 @@
-install_data('org.gnome.gedit.svg',
-  install_dir: join_paths(datadir, 'icons', 'hicolor', 'scalable', 'apps'),
+install_data(
+  'org.gnome.gedit.svg',
+  install_dir: join_paths(
+    get_option('prefix'),
+    get_option('datadir'),
+    'icons/hicolor/scalable/apps'
+  )
 )
 
-install_data('org.gnome.gedit-symbolic.svg',
-  install_dir: join_paths(datadir, 'icons', 'hicolor', 'symbolic', 'apps'),
+install_data(
+  'org.gnome.gedit-symbolic.svg',
+  install_dir: join_paths(
+    get_option('prefix'),
+    get_option('datadir'),
+    'icons/hicolor/symbolic/apps'
+  )
 )
 
 install_man('gedit.1')