systemd: Stop targets when unneeded

This is not a big deal normally because the BMC will powercycle, but
these targets should stop after being executed so they can be started a
second time if desired.

Change-Id: Ia8f4131db719c80b352cdac3b1161d344a1c955c
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/gbmc-psu-hardreset-pre.target b/gbmc-psu-hardreset-pre.target
index 6eb0a26..d7aa2a2 100644
--- a/gbmc-psu-hardreset-pre.target
+++ b/gbmc-psu-hardreset-pre.target
@@ -1,4 +1,5 @@
 [Unit]
 Description=Sys PSU Hard Reset
+StopWhenUnneeded=true
 Wants=gbmc-psu-hardreset-time.service
 After=gbmc-psu-hardreset-time.service
diff --git a/gbmc-psu-hardreset.target b/gbmc-psu-hardreset.target
index 6501a3c..4b9133d 100644
--- a/gbmc-psu-hardreset.target
+++ b/gbmc-psu-hardreset.target
@@ -1,4 +1,5 @@
 [Unit]
 Description=Sys PSU Hard Reset
+StopWhenUnneeded=true
 Wants=gbmc-psu-hardreset-pre.target
 After=gbmc-psu-hardreset-pre.target