bnx2x: Fix compiler warnings

Fix the following compiler warnings:

 - drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c:2908:3: warning: comparison
   of distinct pointer types lacks a cast [enabled by default]
 - drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c:1709:7: warning: comparison
   of distinct pointer types lacks a cast [enabled by default]

Signed-off-by: Joren Van Onder <joren.vanonder@gmail.com>
Acked-By: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>