Added "drivers" to cells that defined ONOS_APPS.

Change-Id: I8e7cbea037ea09504662fb17ef328b547d21050a
diff --git a/tools/test/cells/office b/tools/test/cells/office
index dd8a5d5..2cd933e 100644
--- a/tools/test/cells/office
+++ b/tools/test/cells/office
@@ -3,5 +3,5 @@
 export ONOS_NIC="10.1.10.*"
 export OC1="10.1.10.223"
 
-export ONOS_APPS="openflow,fwd,proxyarp,mobility"
+export ONOS_APPS="drivers,openflow,fwd,proxyarp,mobility"