IB/ipoib: remove the unnecessary memory free

In the function ipoib_cm_nonsrq_init_rx, the memory is not
allocated successfully. It is not necessary to free it.

CC: Joe Jin <joe.jin@oracle.com>
CC: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>