Staging: hv: remove OnChildDeviceDestroy vmbus_driver callback

No one ever calls it so get rid of it, it's pointless.

Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/vmbus_api.h

@@ -122,7 +122,6 @@ struct vmbus_driver {
 	struct hv_driver Base;
 
 	/* Set by the caller */
-	void (*OnChildDeviceDestroy)(struct hv_device *device);
 	int (*OnChildDeviceAdd)(struct hv_device *RootDevice,
 				struct hv_device *ChildDevice);
 	void (*OnChildDeviceRemove)(struct hv_device *device);

drivers/staging/hv/vmbus_drv.c

@@ -69,7 +69,6 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id);
 static void vmbus_device_release(struct device *device);
 static void vmbus_bus_release(struct device *device);
 
-static void vmbus_child_device_destroy(struct hv_device *device_obj);
 static int vmbus_child_device_register(struct hv_device *root_device_obj,
 				       struct hv_device *child_device_obj);
 static void vmbus_child_device_unregister(struct hv_device *child_device_obj);
@@ -298,7 +297,6 @@ static int vmbus_bus_init(int (*drv_init)(struct hv_driver *drv))
 	 * Set this up to allow lower layer to callback to add/remove child
 	 * devices on the bus
 	 */
-	vmbus_drv_obj->OnChildDeviceDestroy = vmbus_child_device_destroy;
 	vmbus_drv_obj->OnChildDeviceAdd = vmbus_child_device_register;
 	vmbus_drv_obj->OnChildDeviceRemove = vmbus_child_device_unregister;
 
@@ -599,13 +597,6 @@ static void vmbus_child_device_unregister(struct hv_device *device_obj)
 		    &device_ctx->device);
 }
 
-/*
- * vmbus_child_device_destroy - Destroy the specified child device on the vmbus.
- */
-static void vmbus_child_device_destroy(struct hv_device *device_obj)
-{
-}
-
 /*
  * vmbus_uevent - add uevent for our device
  *
@@ -848,7 +839,6 @@ static void vmbus_device_release(struct device *device)
 {
 	struct vm_device *device_ctx = device_to_vm_device(device);
 
-	/* vmbus_child_device_destroy(&device_ctx->device_obj); */
 	kfree(device_ctx);
 
 	/* !!DO NOT REFERENCE device_ctx anymore at this point!! */