Use dib helper script to determine init system

diskimage-builder provides a helper script + env variable
to determine, which init system is used. We should use them
in elements instead of manual checks after update of raring
cloud images broke "if [ -d /etc/systemd/system ]" test.

Related-Bug: #1251610

Change-Id: I6d27491302ff0c4c6de82d6d60fc80e83fec519e

elements/apache2/post-install.d/15-apache2

@@ -1,6 +1,6 @@
 #!/bin/bash
 set -eux
 
-if [ -d /etc/systemd/system ]; then
+if [ "$DIB_INIT_SYSTEM" == "systemd" ]; then
   systemctl enable httpd.service
 fi

elements/bm-dnsmasq/install.d/81-bm-dnsmasq

@@ -64,8 +64,8 @@ eof
 
 }
 
-if [ -d /etc/init ]; then
+if [ "$DIB_INIT_SYSTEM" == "upstart" ]; then
   install_dnsmasq_upstart
-elif [ -d /lib/systemd/system ]; then
+elif [ "$DIB_INIT_SYSTEM" == "systemd" ]; then
   install_dnsmasq_systemd
 fi

elements/os-collect-config/install.d/10-os-collect-config

@@ -11,8 +11,7 @@ cat > /etc/os-collect-config.conf <<eof
 command=os-refresh-config
 eof
 
-# Upstart
-if [ -d /etc/init ] ; then
+if [ "$DIB_INIT_SYSTEM" == "upstart" ] ; then
     cat > /etc/init/os-collect-config.conf <<eof
 start on runlevel [2345]
 stop on runlevel [016]
@@ -20,8 +19,7 @@ respawn
 exec os-collect-config
 eof
 
-# Systemd
-elif [ -d /lib/systemd/system ] ; then
+elif [ "$DIB_INIT_SYSTEM" == "systemd" ] ; then
     cat > /lib/systemd/system/os-collect-config.service <<eof
 [Unit]
 Description=Collect metadata and run hook commands.

elements/os-svc-install/bin/os-svc-daemon

@@ -151,9 +151,10 @@ EOF
 }
 
 # TODO: SysV init fallback support
-if [ -d /etc/init ]; then
+DIB_INIT_SYSTEM=$(dib-init-system)
+if [ "$DIB_INIT_SYSTEM" == "upstart" ]; then
   install_upstart $SERVICENAME $RUNAS $RUNCMD $*
-elif [ -d /etc/systemd/system ]; then
+elif [ "$DIB_INIT_SYSTEM" == "systemd" ]; then
   if [ "$POSTSTART" != "$DEFAULT_POSTSTART" ] ; then
       echo "WARNING: post start is ignored with systemd." >&2
   fi

elements/qpidd/install.d/20-qpidd

@@ -27,8 +27,8 @@ eof
 }
 
 
-if [ -d /etc/init ]; then
+if [ "$DIB_INIT_SYSTEM" == "upstart" ]; then
     install_qpidd_upstart
-elif [ -d /lib/systemd/system ]; then
+elif [ "$DIB_INIT_SYSTEM" == "systemd" ]; then
     install_qpidd_systemd
 fi

elements/tripleo-cd/install.d/10-tripleo-cd

@@ -1,8 +1,7 @@
 #!/bin/bash
 set -eux
 
-# Upstart
-if [ -d /etc/init ] ; then
+if [ "$DIB_INIT_SYSTEM" == "upstart" ] ; then
     cat > /etc/init/tripleo-cd.conf <<eof
 start on runlevel [2345]
 stop on runlevel [016]
@@ -10,8 +9,7 @@ respawn
 exec tripleo-cd.sh
 eof
 
-# Systemd
-elif [ -d /lib/systemd/system ] ; then
+elif [ "$DIB_INIT_SYSTEM" == "systemd" ] ; then
     cat > /lib/systemd/system/os-collect-config.service <<eof
 [Unit]
 Description=Deploy an overcloud forever.