Merge remote-tracking branch 'mreitz/block' into queue-block

* mreitz/block:
  block/vpc: remove disabled code from get_sector_offset
  block/vpc: rename footer->size -> footer->current_size
  block/vpc: make calculate_geometry spec conform
  vpc: Ignore geometry for large images
  block/vpc: optimize vpc_co_get_block_status
  block: Drop bdrv_find
  blockdev: Convert bdrv_find to blk_by_name
  migration: Convert bdrv_find to blk_by_name
  monitor: Convert bdrv_find to blk_by_name
  iotests: Test non-self-referential qcow2 refblocks
  iotests: Add tests for refcount table growth
  qcow2: Respect new_block in alloc_refcount_block()