bna: remove set but not used variable 'pgoff'

drivers/net/ethernet/brocade/bna/bfa_ioc.c: In function
‘bfa_ioc_fwver_clear’:
drivers/net/ethernet/brocade/bna/bfa_ioc.c:1127:13: warning: variable
‘pgoff’ set but not used [-Wunused-but-set-variable]

It is never used, and so can be removed.

Signed-off-by: yu kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>