[SCSI] qla2xxx: Add cond_resched() calls during HBA flash manipulation.

We're observing soft lockups during HBA FLASH retrieval and
update.  Add cond_resched() each time around the tight-loops
during flash read()s/write()s.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>