Fix build with latest ndn-cxx

Change-Id: I850fc92a0bb50632ba5b5bacab6cedb321754db1
diff --git a/wscript b/wscript
index d2c16f6..57129d9 100644
--- a/wscript
+++ b/wscript
@@ -34,7 +34,7 @@
     conf.find_program(['pkgconf', 'pkg-config'], var='PKGCONFIG')
 
     pkg_config_path = os.environ.get('PKG_CONFIG_PATH', f'{conf.env.LIBDIR}/pkgconfig')
-    conf.check_cfg(package='libndn-cxx', args=['libndn-cxx >= 0.8.1', '--cflags', '--libs'],
+    conf.check_cfg(package='libndn-cxx', args=['libndn-cxx >= 0.9.0', '--cflags', '--libs'],
                    uselib_store='NDN_CXX', pkg_config_path=pkg_config_path)
 
     conf.check_sqlite3()