nfd: Add missing dependencies

Refs: #2013 (http://redmine.named-data.net/issues/2013)
diff --git a/nfd/Makefile b/nfd/Makefile
index d9d27b4..b1db703 100644
--- a/nfd/Makefile
+++ b/nfd/Makefile
@@ -11,6 +11,6 @@
 VERSION=0.2.0-0
 
 # PPA version
-PPA_VERSION=1
+PPA_VERSION=2
 
 include ../packaging.mk