scsi: fnic: Move flush_work initialization out of if block

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

scsi: fnic: Move flush_work initialization out of if block

After commit 379a58caa199 ("scsi: fnic: Move fnic_fnic_flush_tx() to a

work queue"), it can happen that a work item is sent to an uninitialized

work queue. This may has the effect that the item being queued is never

actually queued, and any further actions depending on it will not

proceed.

The following warning is observed while the fnic driver is loaded:

kernel: WARNING: CPU: 11 PID: 0 at ../kernel/workqueue.c:1524 __queue_work+0x373/0x410

kernel: <IRQ>

kernel: queue_work_on+0x3a/0x50

kernel: fnic_wq_copy_cmpl_handler+0x54a/0x730 [fnic 62fbff0c42e7fb825c60a55cde2fb91facb2ed24]

kernel: fnic_isr_msix_wq_copy+0x2d/0x60 [fnic 62fbff0c42e7fb825c60a55cde2fb91facb2ed24]

kernel: __handle_irq_event_percpu+0x36/0x1a0

kernel: handle_irq_event_percpu+0x30/0x70

kernel: handle_irq_event+0x34/0x60

kernel: handle_edge_irq+0x7e/0x1a0

kernel: __common_interrupt+0x3b/0xb0

kernel: common_interrupt+0x58/0xa0

kernel: </IRQ>

It has been observed that this may break the rediscovery of Fibre

Channel devices after a temporary fabric failure.

This patch fixes it by moving the work queue initialization out of

an if block in fnic_probe().