bnx2x: Changes with storage & MAC macros

Rearrange macros to query for storage-only modes in different MF environment.
Improves the readibility and maintainability of the code. E.g.:
	-	if (IS_MF_STORAGE_SD(bp) || IS_MF_FCOE_AFEX(bp))
	+	if (IS_MF_STORAGE_ONLY(bp))

In addition, this removes the need for bnx2x_is_valid_ether_addr().

Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>