[PATCH] PCI: fix stale PCI pm docs

These functions are intended for use by individual drivers, and are defined in 

struct pci_driver:

        int  (*save_state) (struct pci_dev *dev, u32 state);

        int  (*suspend) (struct pci_dev *dev, u32 state);

        int  (*suspend) (struct pci_dev *dev, pm_message_t state);

        int  (*resume) (struct pci_dev *dev);

        int  (*enable_wake) (struct pci_dev *dev, u32 state, int enable);

save_state

----------

Usage:

if (dev->driver && dev->driver->save_state)

	dev->driver->save_state(dev,state);

The driver should use this callback to save device state. It should take into

account the current state of the device and the requested state in order to

avoid any unnecessary operations.

For example, a video card that supports all 4 states (D0-D3), all controller

context is preserved when entering D1, but the screen is placed into a low power

state (blanked). 

The driver can also interpret this function as a notification that it may be

entering a sleep state in the near future. If it knows that the device cannot

enter the requested state, either because of lack of support for it, or because

the device is middle of some critical operation, then it should fail.

This function should not be used to set any state in the device or the driver

because the device may not actually enter the sleep state (e.g. another driver

later causes causes a global state transition to fail).

Note that in intermediate low power states, a device's I/O and memory spaces may

be disabled and may not be available in subsequent transitions to lower power

states.

        int  (*enable_wake) (struct pci_dev *dev, pci_power_t state, int enable);

suspend