Avoid deprecated ndn-cxx functions

Change-Id: Ib148262999a691760821a2ce1c05a5e6332e7e34
diff --git a/wscript b/wscript
index b2b21f9..b3e2e4d 100644
--- a/wscript
+++ b/wscript
@@ -5,7 +5,6 @@
 
 VERSION = '0.1.0'
 APPNAME = 'ndn-nac'
-PACKAGE_BUGREPORT = 'https://redmine.named-data.net/projects/nac'
 GIT_TAG_PREFIX = 'nac-'
 
 def options(opt):
@@ -31,8 +30,9 @@
 
     conf.find_program('dot', var='DOT', mandatory=False)
 
-    conf.check_cfg(package='libndn-cxx', args=['--cflags', '--libs'], uselib_store='NDN_CXX',
-                   pkg_config_path=os.environ.get('PKG_CONFIG_PATH', '%s/pkgconfig' % conf.env.LIBDIR))
+    pkg_config_path = os.environ.get('PKG_CONFIG_PATH', f'{conf.env.LIBDIR}/pkgconfig')
+    conf.check_cfg(package='libndn-cxx', args=['libndn-cxx >= 0.8.0', '--cflags', '--libs'],
+                   uselib_store='NDN_CXX', pkg_config_path=pkg_config_path)
 
     boost_libs = ['system', 'program_options']
     if conf.env.WITH_TESTS: