qed: Pass src/dst sizes when interacting with MFW

The driver interaction with management firmware involves a union
of all the data-members relating to the commands the driver prepares.

Current interface assumes the caller always passes such a union -
but thats cumbersome as well as risky [chancing a stack corruption
in case caller accidentally passes a smaller member instead of union].

Change implementation so that caller could pass a pointer to any
of the members instead of the union.

Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qlogic/qed/qed_mcp.h b/drivers/net/ethernet/qlogic/qed/qed_mcp.h
index 0f7b268..f63693d 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_mcp.h
+++ b/drivers/net/ethernet/qlogic/qed/qed_mcp.h
@@ -516,8 +516,10 @@ struct qed_mcp_info {
 struct qed_mcp_mb_params {
 	u32			cmd;
 	u32			param;
-	union drv_union_data	*p_data_src;
-	union drv_union_data	*p_data_dst;
+	void			*p_data_src;
+	u8			data_src_size;
+	void			*p_data_dst;
+	u8			data_dst_size;
 	u32			mcp_resp;
 	u32			mcp_param;
 };