[MLX4] added Hibernate/Standby support. (mlnx: 2906)

[MLX4] added Hibernate/Standby support. (mlnx: 2906)

Mellanox HCA cards do not have Power Management support so far.
So MLX4 driver resets the card on power-down  and starts its back on power-up.
Pay attention, one can go to Standby/Hibernate only when there is no running IB applications (including WSD).
Otherwise he will get an error window with a message like: "Driver mlx4_hca.sys refuses to go Hibernate/Standby".
MTHCA driver behaves upon Hibernate/Standby the same way.

git-svn-id: svn://openib.tc.cornell.edu/gen1@1462 ad392aa1-c5ef-ae45-8dd8-e69d62a5ef86