[SCSI] qla2xxx: Correct locking during NVRAM manipulation.

Commit 2c96d8d0 pushed the
acquisition of hardware_lock to too fine a level, which in turn
will cause problems with cond_resched()s added with
40a2e34a.

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