Staging: hv: Get rid of the drv field in struct hv_device

Now, we can rid of the drv field in struct hv_device.
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NAbhishek Kane <v-abkane@microsoft.com>
Signed-off-by: NHank Janssen <hjanssen@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/vmbus_api.h

@@ -103,9 +103,6 @@ struct hv_driver {
 
 /* Base device object */
 struct hv_device {
-	/* the driver for this device */
-	struct hv_driver *drv;
-
 	char name[64];
 
 	struct work_struct probe_failed_work_item;