systemd: add WantedBy=nfd.service to units that bind to nfd

Change-Id: I09c0f05a22985b9182e75feaae0d97791827675e
Refs: #4594
diff --git a/systemd/ndn-autoconfig-client.service.in b/systemd/ndn-autoconfig-client.service.in
index 2eaf3d4..668c4fb 100644
--- a/systemd/ndn-autoconfig-client.service.in
+++ b/systemd/ndn-autoconfig-client.service.in
@@ -60,3 +60,4 @@
 
 [Install]
 WantedBy=multi-user.target
+WantedBy=nfd.service
diff --git a/systemd/ndn-autoconfig-server.service.in b/systemd/ndn-autoconfig-server.service.in
index 3403109..7ddf021 100644
--- a/systemd/ndn-autoconfig-server.service.in
+++ b/systemd/ndn-autoconfig-server.service.in
@@ -61,3 +61,4 @@
 
 [Install]
 WantedBy=multi-user.target
+WantedBy=nfd.service
diff --git a/systemd/nfd-autoreg.service.in b/systemd/nfd-autoreg.service.in
index e245700..560c291 100644
--- a/systemd/nfd-autoreg.service.in
+++ b/systemd/nfd-autoreg.service.in
@@ -61,3 +61,4 @@
 
 [Install]
 WantedBy=multi-user.target
+WantedBy=nfd.service