nfd: Ensure that /var/lib/ndn folder is owned by ndn user

Refs: #2471
diff --git a/nfd/Makefile b/nfd/Makefile
index 185ff44..1844a8e 100644
--- a/nfd/Makefile
+++ b/nfd/Makefile
@@ -11,6 +11,6 @@
 VERSION=0.3.0
 
 # PPA version
-PPA_VERSION=1
+PPA_VERSION=2
 
 include ../packaging.mk