scsi: lpfc: Add auto select on IRQ_POLL

lpfc depends on irq_poll library, but it is not selected automatically.
When irq_poll is not selected, compiling it can run into following error

ERROR: modpost: "irq_poll_init" [drivers/scsi/lpfc/lpfc.ko] undefined!
ERROR: modpost: "irq_poll_sched" [drivers/scsi/lpfc/lpfc.ko] undefined!
ERROR: modpost: "irq_poll_complete" [drivers/scsi/lpfc/lpfc.ko] undefined!

Link: https://lore.kernel.org/r/20210126000554.309858-1-ztong0001@gmail.com
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>