block/qapi: Let bdrv_query_image_info() recurse

block/qapi: Let bdrv_query_image_info() recurse

There is no real reason why bdrv_query_image_info() should generally not
recurse.  The ImageInfo struct has a pointer to the backing image, so it
should generally be filled, unless the caller explicitly opts out.

This moves the recursing code from bdrv_block_device_info() into
bdrv_query_image_info().

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220620162704.80987-7-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>