qlcnic: Fix for flash update failure on 83xx adapter

Flash update routine was improperly checking register read API return value.
Modify register read API and perform proper error check.

Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
10 files changed