net/mlx4_core: need to call close fw if alloc icm is called twice

If mlx4_enable_sriov is called by adapter without this
feature MLX4_DEV_CAP_FLAG2_SYS_EQS then during this path the function alloc
icm is called twice without freeing the structures from the first time.

Acked-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Carol L Soto <clsoto@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>