bare-metal-host-monitor: Use service type notify

We want to be able to start other services after this daemon has
finished its startup code. So, this commit updates the host-gpio-monitor
code to notify systemd when the initialization is done.

Tested:
Set the bare metal flag /var/google/config-package/enable-bm.flag
Did a power cycle, and confirmed the services started in the expected
order.

Change-Id: I51d1aed7509795852f5873f71ae6ba57401ae6b9
Signed-off-by: John Wedig <johnwedig@google.com>
diff --git a/subprojects/bare-metal-host-monitor/host-gpio-monitor@.service.in b/subprojects/bare-metal-host-monitor/host-gpio-monitor@.service.in
index e4accf2..3e1f6a1 100644
--- a/subprojects/bare-metal-host-monitor/host-gpio-monitor@.service.in
+++ b/subprojects/bare-metal-host-monitor/host-gpio-monitor@.service.in
@@ -5,6 +5,7 @@
 After=xyz.openbmc_project.Chassis.Control.Power@%i.service
 
 [Service]
+Type=notify
 Restart=always
 ExecStart=@@BIN@ host_gpio_monitor --host_label %i