Task abort can take 2 paths: 1) serial/synchronous abort where the calling
thread will put to sleep, wait for completion and free cmd resource.  2) async
abort where the cmd free will be free by the completion thread.  For path 2,
driver is freeing the SRB too early.

Fixes: f6145e86 ("scsi: qla2xxx: Fix race between switch cmd completion and timeout")
Cc: stable@vger.kernel.org # 4.19
Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>