build: Fix compatibility with Python 3

Change-Id: I7a1b98c38c2ed3a147c7b0e6c7b79d2723f2a3ba
Refs: #3493
diff --git a/.waf-tools/doxygen.py b/.waf-tools/doxygen.py
index ac8c70b..6d8066b 100644
--- a/.waf-tools/doxygen.py
+++ b/.waf-tools/doxygen.py
@@ -85,7 +85,7 @@
 
 			# Override with any parameters passed to the task generator
 			if getattr(self.generator, 'pars', None):
-				for k, v in self.generator.pars.iteritems():
+				for k, v in self.generator.pars.items():
 					self.pars[k] = v
 
 			self.doxy_inputs = getattr(self, 'doxy_inputs', [])
diff --git a/tests/other/wscript b/tests/other/wscript
index 805735c..6398f32 100644
--- a/tests/other/wscript
+++ b/tests/other/wscript
@@ -27,7 +27,7 @@
 top = '../..'
 
 def build(bld):
-   for module, name in {"cs-benchmark": "CS Benchmark"}.iteritems():
+   for module, name in {"cs-benchmark": "CS Benchmark"}.items():
        # main()
        bld(target='unit-tests-%s-main' % module,
            name='unit-tests-%s-main' % module,
diff --git a/tests/wscript b/tests/wscript
index 3b9e628..3d080aa 100644
--- a/tests/wscript
+++ b/tests/wscript
@@ -42,7 +42,7 @@
 
         for module, name in {"core": "NFD Core Tests",
                              "daemon": "NFD Daemon Tests",
-                             "rib": "NFD RIB Tests"}.iteritems():
+                             "rib": "NFD RIB Tests"}.items():
             # main()
             bld(target='unit-tests-%s-main' % module,
                 name='unit-tests-%s-main' % module,