bnx2: Try to recover from PCI block reset

bnx2: Try to recover from PCI block reset

If the PCI block has reset, the memory enable bit will be reset and
the device will not respond to MMIO access.  bnx2_reset_task() currently
will not recover when this happens.  Add code to detect this condition
and restore the PCI state.  This scenario has been reported by some
users.

(cherry picked from commit efdfad3205403e1d1c5c0bdcbdb647ddd89bfaa3)
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Joe Jin <joe.jin@oracle.com>