vhost-iotlb: fix vhost_iotlb_itree_next() documentation

This patch contains trivial changes for the vhost_iotlb_itree_next()
documentation, fixing the function name and the description of
first argument (@map).
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20200825130543.43308-1-sgarzare@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vhost/iotlb.c

@@ -159,8 +159,8 @@ vhost_iotlb_itree_first(struct vhost_iotlb *iotlb, u64 start, u64 last)
 EXPORT_SYMBOL_GPL(vhost_iotlb_itree_first);
 
 /**
- * vhost_iotlb_itree_first - return the next overlapped range
- * @iotlb: the IOTLB
+ * vhost_iotlb_itree_next - return the next overlapped range
+ * @map: the starting map node
  * @start: start of IOVA range
  * @end: end of IOVA range
  */