bnx2fc: Do not log error for netevents that need no action

Do not log error for netevents that need no action such as
NETDEV_REGISTER 0x0005, NETDEV_CHANGEADDR, and NETDEV_CHANGENAME.
It results in logging error messages such as these

[   35.315872] bnx2fc: Unknown netevent 5
[   35.315935] bnx2fc: Unknown netevent 8
[   35.353866] bnx2fc: Unknown netevent 10

and generating bug reports.
Remove logging this message as an ERROR instead of turning them into
either DEBUG or INFO level messages.

Signed-off-by: Shirish Pargaonkar <spargaonkar@suse.com>
Acked-by: Eddie Wai <eddie.wai@broadcom.com>
Acked-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>