fsi-scan: make systemd wants relationship

systemd recommends a wants vs. requires relationship so this is a small
step in that direction for OpenBMC.

This also alleviates a common pain point in bringup where FSI is not
working properly or a FSI device is not present in the system. With a
requires relationship, the chassis poweron target fails. What a user
really wants is for the power on to still succeed.

Other firmware, which requires FSI, will detect issues during the host
boot and take proper actions.

Tested:
Injected fail into fsi-scan service and verified with this change that
chassis power on still succeeded.

(From meta-openpower rev: 58b758a36c28544ee31b75a1aa7dddd5d0fe355c)

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I6615f81778430dd5d855149b97cba70fbba5f993
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-openpower/recipes-phosphor/fsi/op-fsi/fsi-scan@.service b/meta-openpower/recipes-phosphor/fsi/op-fsi/fsi-scan@.service
index d8f2888..dd837ef 100644
--- a/meta-openpower/recipes-phosphor/fsi/op-fsi/fsi-scan@.service
+++ b/meta-openpower/recipes-phosphor/fsi/op-fsi/fsi-scan@.service
@@ -14,4 +14,4 @@
 RemainAfterExit=yes
 
 [Install]
-RequiredBy=obmc-chassis-poweron@%i.target
+WantedBy=obmc-chassis-poweron@%i.target