Ignore stmf target must be offline exception

Patch to ignore

"NexentaJSONException: : Unable to add member to targetgroup:
  stmfadm: STMF target must be offline"

This error happens when targetgroup is already configured and busy.

fixed bug 1209305

Change-Id: I2441118c0968a7a373b5990db6782129291c3051
Merge "Ignore stmf target must be offline exception"