ensure sbe started after pre target

For the synchronization targets to work correctly, a service must Wants
and After it. The Wants was missing here so there is a race condition
where this may run before the FSI scan service has completed.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I164c2af8d36fdc495ea3304fc8aec2bcd5756241
diff --git a/recipes-phosphor/host/op-host-control/start_host@.service b/recipes-phosphor/host/op-host-control/start_host@.service
index 825275a..aa12be3 100644
--- a/recipes-phosphor/host/op-host-control/start_host@.service
+++ b/recipes-phosphor/host/op-host-control/start_host@.service
@@ -1,5 +1,6 @@
 [Unit]
 Description=Start host%i SBE
+Wants=obmc-host-start-pre@%i.target
 After=obmc-host-start-pre@%i.target
 Wants=obmc-host-starting@%i.target
 Before=obmc-host-starting@%i.target