[pci] Remove ->save_state() from struct pci_driver.

It is not called, and unused.

include/linux/pci.h

@@ -515,7 +515,6 @@ struct pci_driver {
 	const struct pci_device_id *id_table;	/* must be non-NULL for probe to be called */
 	int  (*probe)  (struct pci_dev *dev, const struct pci_device_id *id);	/* New device inserted */
 	void (*remove) (struct pci_dev *dev);	/* Device removed (NULL if not a hot-plug capable driver) */
-	int  (*save_state) (struct pci_dev *dev, u32 state);    /* Save Device Context */
 	int  (*suspend) (struct pci_dev *dev, u32 state);	/* Device suspended */
 	int  (*resume) (struct pci_dev *dev);	                /* Device woken up */
 	int  (*enable_wake) (struct pci_dev *dev, u32 state, int enable);   /* Enable wake event */