VOL-1371 Allow mfr description to be VOLTHA Project so onos can figure out this is a voltha olt

Currently the hardware manufacture is being set which does not match onos-drivers.xml pattern matching
This prevents auto driver discovery from working (in seba/xos especially) and loads the default driver
breaking double-vlan subscriber flows.

Change-Id: Ice58b5e9378b3308eba158afc20d496d2115f724
diff --git a/voltha/adapters/openolt/openolt_device.py b/voltha/adapters/openolt/openolt_device.py
index d16dbca..1381110 100644
--- a/voltha/adapters/openolt/openolt_device.py
+++ b/voltha/adapters/openolt/openolt_device.py
@@ -172,9 +172,6 @@
                 )
             ),
             desc=ofp_desc(
-                mfr_desc=mfr_desc,
-                hw_desc=hw_desc,
-                sw_desc=sw_desc,
                 serial_num=serial_number
             )
         )