PRIu32 is the format string specifier for uint32_t, let's use it.
Variables ->block_size, ->n_blocks, and i are all uint32_t.
Suggested-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>