ide: fix refcounting in device drivers

During host driver module removal del_gendisk() results in a final
put on drive->gendev and freeing the drive by drive_release_dev().

Convert device drivers from using struct kref to use struct device
so device driver's object holds reference on ->gendev and prevents
drive from prematurely going away.

Also fix ->remove methods to not erroneously drop reference on a
host driver by using only put_device() instead of ide*_put().

Reported-by: Stanislaw Gruszka <stf_xl@wp.pl>
Tested-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 194da5a..fe235b6 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -663,7 +663,7 @@
 #define to_ide_device(dev)		container_of(dev, ide_drive_t, gendev)
 
 #define to_ide_drv(obj, cont_type)	\
-	container_of(obj, struct cont_type, kref)
+	container_of(obj, struct cont_type, dev)
 
 #define ide_drv_g(disk, cont_type)	\
 	container_of((disk)->private_data, struct cont_type, driver)