ide: HPA detect from resume

Currently when system which have HPA require HPA to be detected and
disabled upon resume from RAM or disk. The current IDE drivers do not do
this nor does libata (obviously it since it doesn't support HPA yet).

I have implemented this into the current IDE drivers and it has been
tested by many others since 7/15/2006 in bug number 6840:

	http://bugzilla.kernel.org/show_bug.cgi?id=6840

and it has been confirmed to work fine with no problems.

bart: added drv != NULL check to generic_ide_suspend()

From: Lee Trager <lt73@cs.drexel.edu>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

include/linux/ide.h

@@ -1001,6 +1001,7 @@ struct ide_driver_s {
 	struct device_driver	gen_driver;
 	int		(*probe)(ide_drive_t *);
 	void		(*remove)(ide_drive_t *);
+	void		(*resume)(ide_drive_t *);
 	void		(*shutdown)(ide_drive_t *);
 #ifdef CONFIG_IDE_PROC_FS
 	ide_proc_entry_t	*proc;