staging: vchi: Get rid of vchi_msg_dequeue()

Nobody uses it. Get rid of it.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20200629150945.10720-15-nsaenzjulienne@suse.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vc04_services/interface/vchi/vchi.h

@@ -93,13 +93,6 @@ extern int32_t vchi_service_release(struct vchi_service *service);
 extern int vchi_queue_kernel_message(struct vchi_service *service, void *data,
 				     unsigned int size);
 
-// Routine to receive a msg from a service
-// Dequeue is equivalent to hold, copy into client buffer, release
-extern int32_t vchi_msg_dequeue(struct vchi_service *service, void *data,
-				uint32_t max_data_size_to_read,
-				uint32_t *actual_msg_size,
-				enum vchi_flags flags);
-
 // Routine to look at a message in place.
 // The message is dequeued, so the caller is left holding it; the descriptor is
 // filled in and must be released when the user has finished with the message.

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_shim.c

@@ -160,45 +160,6 @@ int32_t vchi_bulk_queue_transmit(struct vchi_service *service,
 }
 EXPORT_SYMBOL(vchi_bulk_queue_transmit);
 
-/***********************************************************
- * Name: vchi_msg_dequeue
- *
- * Arguments:  struct vchi_service *service,
- *             void *data,
- *             uint32_t max_data_size_to_read,
- *             uint32_t *actual_msg_size
- *             enum vchi_flags flags
- *
- * Description: Routine to dequeue a message into the supplied buffer
- *
- * Returns: int32_t - success == 0
- *
- ***********************************************************/
-int32_t vchi_msg_dequeue(struct vchi_service *service, void *data,
-			 uint32_t max_data_size_to_read,
-			 uint32_t *actual_msg_size, enum vchi_flags flags)
-{
-	struct vchiq_header *header;
-
-	WARN_ON((flags != VCHI_FLAGS_NONE) &&
-		(flags != VCHI_FLAGS_BLOCK_UNTIL_OP_COMPLETE));
-
-	if (flags == VCHI_FLAGS_NONE)
-		if (vchiu_queue_is_empty(&service->queue))
-			return -1;
-
-	header = vchiu_queue_pop(&service->queue);
-
-	memcpy(data, header->data, header->size < max_data_size_to_read ?
-		header->size : max_data_size_to_read);
-
-	*actual_msg_size = header->size;
-
-	vchiq_release_message(service->handle, header);
-
-	return 0;
-}
-EXPORT_SYMBOL(vchi_msg_dequeue);
 
 /***********************************************************
  * Name: vchi_held_msg_release