[tracker] meson: Fix use of nonexistant 'default' keyword

[Sam Thursfield <sthursfield src gnome org>]

commit b5dd753f959efd7af42bcab76625bf8ef06dbdb3
Author: Sam Thursfield <sam thursfield codethink co uk>
Date:   Tue Oct 31 14:06:09 2017 +0000

    meson: Fix use of nonexistant 'default' keyword
    
    The correct keyword is 'value'.

 meson_options.txt |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/meson_options.txt b/meson_options.txt
index 1624c4a..55cc2e5 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -41,9 +41,9 @@ option('stemmer', type: 'combo', choices: ['auto', 'no', 'yes'], value: 'no',
 option('unicode_support', type: 'combo', choices: ['icu', 'unistring', 'auto'], value: 'auto',
        description: 'Unicode support library to use')
 
-option('bash_completion', type: 'string', default: 'yes',
+option('bash_completion', type: 'string', value: 'yes',
        description: 'Directory to install Bash completion files (or "yes" for default directory, "no" to 
disable installation')
-option('dbus_services', type: 'string', default: '',
+option('dbus_services', type: 'string', value: '',
        description: 'Directory to install D-Bus .service files (leave blank to use the value from 
dbus-1.pc)')
-option('systemd_user_services', type: 'string', default: 'yes',
+option('systemd_user_services', type: 'string', value: 'yes',
        description: 'Directory to install systemd user .service files (or "yes" for default directory, "no" 
to disable installation)')