Ensure FSI scan runs before services that use FSI

The FSI scan must be done before start_host and vcs_workaround
run in order for them to work propertly.

Change-Id: I1305a65763ba35721d5655f1f3e6c2d8af5fdc71
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/common/recipes-phosphor/chassis/obmc-fsi-scan/fsi-scan@.service b/common/recipes-phosphor/chassis/obmc-fsi-scan/fsi-scan@.service
index ac37004..8f94e28 100644
--- a/common/recipes-phosphor/chassis/obmc-fsi-scan/fsi-scan@.service
+++ b/common/recipes-phosphor/chassis/obmc-fsi-scan/fsi-scan@.service
@@ -2,6 +2,8 @@
 Description=Scan FSI devices
 Wants=obmc-power-on@%i.target
 After=obmc-power-on@%i.target
+Wants=obmc-host-start-pre@%i.target
+Before=obmc-host-start-pre@%i.target
 Conflicts=obmc-power-chassis-off@%i.target
 
 [Service]