scsi: qla2xxx: Fix a recently introduced kernel warning

According to the firmware documentation a status type 0 IOCB can be
followed by one or more status continuation type 0 IOCBs. Hence do not
complain if the completion function is not called from inside the status
type 0 IOCB handler.

WARNING: CPU: 10 PID: 425 at drivers/scsi/qla2xxx/qla_isr.c:2784
qla2x00_status_entry.isra.7+0x484/0x17b0 [qla2xxx]
CPU: 10 PID: 425 Comm: kworker/10:1 Tainted: G            E     5.3.0-rc4-next-20190813-autotest-autotest #1
Workqueue: qla2xxx_wq qla25xx_free_rsp_que [qla2xxx]
Call Trace:
 qla2x00_status_entry.isra.7+0x1484/0x17b0 [qla2xxx] (unreliable)
 qla24xx_process_response_queue+0x7d8/0xbd0 [qla2xxx]
 qla25xx_free_rsp_que+0x1a0/0x220 [qla2xxx]
 process_one_work+0x25c/0x520
 worker_thread+0x8c/0x5e0
 kthread+0x154/0x1a0
 ret_from_kernel_thread+0x5c/0x7c

Cc: Himanshu Madhani <hmadhani@marvell.com>
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_isr.c

@@ -2780,8 +2780,6 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
 
 	if (rsp->status_srb == NULL)
 		sp->done(sp, res);
-	else
-		WARN_ON_ONCE(true);
 }
 
 /**