net/rds: Fix error handling in rds_ib_add_one()

rds_ibdev:ipaddr_list and rds_ibdev:conn_list are initialized
after allocation some resources such as protection domain.
If allocation of such resources fail, then these uninitialized
variables are accessed in rds_ib_dev_free() in failure path. This
can potentially crash the system. The code has been updated to
initialize these variables very early in the function.

Signed-off-by: Dotan Barak <dotanb@dev.mellanox.co.il>
Signed-off-by: Sudhakar Dindukurti <sudhakar.dindukurti@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>