meta-ibm: move all services to multi-user.target

Instead of obmc-standby.target, use multi-user.target.

Change-Id: I0d7357c615ed83d2d172d18fce19df71b1c70847
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/meta-witherspoon/recipes-phosphor/power/witherspoon-pfault-analysis/witherspoon-power-supply-monitor@.service b/meta-witherspoon/recipes-phosphor/power/witherspoon-pfault-analysis/witherspoon-power-supply-monitor@.service
index ba4e368..56e2d21 100644
--- a/meta-witherspoon/recipes-phosphor/power/witherspoon-pfault-analysis/witherspoon-power-supply-monitor@.service
+++ b/meta-witherspoon/recipes-phosphor/power/witherspoon-pfault-analysis/witherspoon-power-supply-monitor@.service
@@ -12,4 +12,4 @@
 SyslogIdentifier=witherspoon-psu-monitor
 
 [Install]
-RequiredBy={SYSTEMD_DEFAULT_TARGET}
+RequiredBy=multi-user.target