mmc: Move process host firmware to own service

The process-host-firmware subcommand waits for the Entity Manager
interface to appear in D-Bus. It's currently run from the mmc-init
script. But if a system does not support Entity Manager, then the init
service never exits, blocking its dependencies like PLDM from starting.

Move the process-host-firmware to its own service file so that if needs
to wait forever, it doesn't interfere with other processes. Need to
start it after the mmc-init so that all the directories are setup before
the symlinks are created.

Tested: Verified on tacoma that the service remains running and PLDM
starts successfully. Verified on rainier that the symlinks are created.

Change-Id: Ia746362e5ff688b972e9b92e9d78f3f5b3623a99
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/mmc/openpower-process-host-firmware.service b/mmc/openpower-process-host-firmware.service
new file mode 100644
index 0000000..a9e419f
--- /dev/null
+++ b/mmc/openpower-process-host-firmware.service
@@ -0,0 +1,12 @@
+[Unit]
+Description=Set POWER host firmware well-known names
+After=org.open_power.Software.Host.Updater.service
+After=obmc-flash-bios-init.service
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/bin/openpower-update-manager process-host-firmware
+
+[Install]
+WantedBy=org.open_power.Software.Host.Updater.service