ARROW-11542: [Rust] fix validity bitmap buffer length count in json reader
ARROW-11542: [Rust] fix validity bitmap buffer length count in json reader

Closes #9436 from houqp/qp_json_read

Authored-by: Qingping Hou <333fd10814a9caf78fd740457f76aba4fa74a157@gmail.com>
Signed-off-by: Andrew Lamb <02e0a999c50b1f88df7a8f5a04e1b76b35ea6a88@nerdnetworks.org>

wesm/arrow,laurentgo/arrow,icexelloss/arrow,laurentgo/arrow,kou/arrow,wesm/arrow,wesm/arrow,kou/arrow,laurentgo/arrow,kou/arrow,apache/arrow,icexelloss/arrow,apache/arrow,icexelloss/arrow,apache/arrow,apache/arrow,laurentgo/arrow,kou/arrow,laurentgo/arrow,cpcloud/arrow,wesm/arrow,apache/arrow,wesm/arrow,cpcloud/arrow,wesm/arrow,icexelloss/arrow,cpcloud/arrow,laurentgo/arrow,apache/arrow,icexelloss/arrow,laurentgo/arrow,laurentgo/arrow,laurentgo/arrow,apache/arrow,apache/arrow,apache/arrow,cpcloud/arrow,laurentgo/arrow,cpcloud/arrow,kou/arrow,icexelloss/arrow,icexelloss/arrow,cpcloud/arrow,apache/arrow,cpcloud/arrow,laurentgo/arrow,laurentgo/arrow,wesm/arrow,kou/arrow,icexelloss/arrow,wesm/arrow,wesm/arrow,kou/arrow,kou/arrow,apache/arrow,icexelloss/arrow,apache/arrow,laurentgo/arrow,kou/arrow,icexelloss/arrow,apache/arrow,kou/arrow,kou/arrow,kou/arrow,icexelloss/arrow,kou/arrow,laurentgo/arrow,apache/arrow,icexelloss/arrow,wesm/arrow,icexelloss/arrow,cpcloud/arrow,icexelloss/arrow,wesm/arrow,wesm/arrow,cpcloud/arrow,laurentgo/arrow,cpcloud/arrow,cpcloud/arrow,wesm/arrow,cpcloud/arrow,cpcloud/arrow,kou/arrow,cpcloud/arrow,wesm/arrow