!2608 [sync] PR-2557: Bluetooth: hci_ldisc: check HCI_UART_PROTO_READY flag in HCIUARTGETPROTO

Merge Pull Request from: @openeuler-sync-bot 
 

Origin pull request: 
https://gitee.com/openeuler/kernel/pulls/2557 
 
PR sync from: Wang Yufen <wangyufen@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/DL6FRJ4FA4JFRKO74RQFMIF4QRYLTDX3/ 
 
https://gitee.com/src-openeuler/kernel/issues/I6YOAU 
 
Link:https://gitee.com/openeuler/kernel/pulls/2608

 

Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>