CVE-2021-47188 scsi: ufs: core: Improve SCSI abort handling

In the Linux kernel, the following vulnerability has been resolved:

scsi: ufs: core: Improve SCSI abort handling

The following has been observed on a test setup:

WARNING: CPU: 4 PID: 250 at drivers/scsi/ufs/ufshcd.c:2737 ufshcd_queuecommand+0x468/0x65c
Call trace:
ufshcd_queuecommand+0x468/0x65c
scsi_send_eh_cmnd+0x224/0x6a0
scsi_eh_test_devices+0x248/0x418
scsi_eh_ready_devs+0xc34/0xe58
scsi_error_handler+0x204/0x80c
kthread+0x150/0x1b4
ret_from_fork+0x10/0x30

That warning is triggered by the following statement:

WARN_ON(lrbp->cmd);

Fix this warning by clearing lrbp->cmd from the abort handler.