bnx2x: use dcb_setapp to manage negotiated application tlvs

With this patch the bnx2x uses the generic dcbnl application tlv list
instead of implementing its own get-app handler. When the driver is
alerted to a change in the DCB negotiated parameters, it calls
dcb_setapp to update the dcbnl application tlvs list making it available
to user mode applications and registered notifiers.   

Signed-off-by: Shmulik Ravid <shmulikr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>