iw_cxgb4: always set iw_cm_id.provider_data

In active side connections, the provider_data field is not
getting set.  This will be used in a subsequent patch to dump
state, so always set it.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>