Ensuring EntityManager starts before all Sensor services

This fix was needed by PSUSensor
However, all of these Sensor services are written in a similar way
All could probably benefit from this similar fix
Adds Requires and After for EntityManager
Also clean up dangling Requires that did not have After
Tested: On PSUSensor only

Signed-off-by: Josh Lehan <krellan@google.com>
Change-Id: Ib132b642b88dfb344b28d27d55dfd89b49e917f4
diff --git a/service_files/xyz.openbmc_project.psusensor.service b/service_files/xyz.openbmc_project.psusensor.service
index 02cdff2..4b22e8c 100644
--- a/service_files/xyz.openbmc_project.psusensor.service
+++ b/service_files/xyz.openbmc_project.psusensor.service
@@ -3,6 +3,7 @@
 StopWhenUnneeded=false
 Requires=xyz.openbmc_project.EntityManager.service
 After=xyz.openbmc_project.EntityManager.service
+
 [Service]
 Restart=always
 RestartSec=5