fix chassis poweron target name

Change-Id: I3da968f6d39d393448d00ab3c063e4d0983cba09
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/architecture/openbmc-systemd.md b/architecture/openbmc-systemd.md
index 9572e05..48e33e3 100644
--- a/architecture/openbmc-systemd.md
+++ b/architecture/openbmc-systemd.md
@@ -158,7 +158,7 @@
 someone starts the same target twice.   If the associated service with that
 target is not running (i.e. RemainAfterExit=no), then the service will be
 executed again.  Think about someone accidentally running the
-obmc-chassis-start@.target twice.  If you execute it when the operating system
+obmc-chassis-poweron@.target twice.  If you execute it when the operating system
 is up and running, and the service which toggles the pgood pin is re-executed,
 you're going to crash your system.  Given this info, the goal should always be
 to write "oneshot" services that have RemainAfterExit set to yes.