[gexiv2] meson: Fix building regression test

[Jens Georg <jensgeorg src gnome org>]

commit dc7c487edf4e201b524c71916b42a48f4609fdd5
Author: Jens Georg <mail jensge org>
Date:   Mon Jun 5 10:46:55 2017 +0200

    meson: Fix building regression test

 test/meson.build |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/test/meson.build b/test/meson.build
index f94f7c7..50593b8 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -10,6 +10,7 @@ test_env = ['G_SLICE=always-malloc',
 
 regression_test = executable('gexiv2-regression', 'gexiv2-regression.c',
                              dependencies : gobject,
+                             include_directories : include_directories('..'),
                              c_args : '-DSAMPLE_PATH="@0@"'.format(test_sample_path),
                              link_with : gexiv2)