[gnome-settings-daemon] build: Fix assertion option

[Iñigo Martínez <inigomartinez src gnome org>]

commit a72c928a477775a7a3885369d05365eaf46ed93f
Author: Iñigo Martínez <inigomartinez gmail com>
Date:   Tue Feb 20 09:50:37 2018 +0100

    build: Fix assertion option
    
    meson has an option called `b_ndebug` to enable or disable
    assertions. This option is used to also enable glib assertions
    by adding `G_DISABLE_ASSERT` macro definition compiler argument.
    
    However, the option is set backwards, because the compiler argument
    is added when the option is false.
    
    This has been changed to add the macro definition that disables
    assertions when `b_ndebug` is true.

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index db3d356d..4f627122 100644
--- a/meson.build
+++ b/meson.build
@@ -74,7 +74,7 @@ endif
 
 # Workaround for meson's bug
 # https://github.com/mesonbuild/meson/pull/1896
-if get_option('b_ndebug') == false
+if get_option('b_ndebug') == true
   common_flags += ['-DG_DISABLE_ASSERT']
 endif