[libgit2-glib] meson: Workaround for meson's b_ndebug

[Iñigo Martínez <inigomartinez src gnome org>]

commit b8e9bfae149eafe9840385ec63b055d4d0aaf92d
Author: Iñigo Martínez <inigomartinez gmail com>
Date:   Mon Jan 22 11:11:51 2018 +0100

    meson: Workaround for meson's b_ndebug
    
    The `b_ndebug` meson's option is used to enable and disable
    assertions. However a recent change[0] has changed its behaviour
    and makes the build to fail.
    
    A workaround has been introduced to avoid this issue.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=792699
    
    [0] https://github.com/mesonbuild/meson/pull/1896

 meson.build |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/meson.build b/meson.build
index c93552d..618d518 100644
--- a/meson.build
+++ b/meson.build
@@ -97,7 +97,9 @@ else
   ]
 endif
 
-if get_option('b_ndebug')
+# Workaround for meson's bug
+# https://github.com/mesonbuild/meson/pull/1896
+if get_option('b_ndebug') == true
   common_flags += [ '-DG_DISABLE_ASSERT' ]
 endif