ndncert: Update

Change-Id: Ia130723cbf8d80f5eb41ea60ff1b1a4316f3b778
diff --git a/ndncert/debian/rules b/ndncert/debian/rules
index 10c8740..1f22ee3 100755
--- a/ndncert/debian/rules
+++ b/ndncert/debian/rules
@@ -11,7 +11,7 @@
 
 LDFLAGS := $(shell dpkg-buildflags --get LDFLAGS)
 CXXFLAGS := $(shell dpkg-buildflags --get CXXFLAGS)
-CXXFLAGS += -std=c++11
+CXXFLAGS += -std=c++14
 LIBDIR := /usr/lib/$(shell dpkg-architecture -qDEB_HOST_MULTIARCH)
 
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