hv_netvsc: copy_to_send buf can be void

Since only caller does not care about return value.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/hyperv/netvsc.c

@@ -701,7 +701,7 @@ static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 	return NETVSC_INVALID_INDEX;
 }
 
-static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
+static void netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 				    unsigned int section_index,
 				    u32 pend_size,
 				    struct hv_netvsc_packet *packet,
@@ -713,7 +713,6 @@ static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 	char *dest = start + (section_index * net_device->send_section_size)
 		     + pend_size;
 	int i;
-	u32 msg_size = 0;
 	u32 padding = 0;
 	u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 		packet->page_buf_cnt;
@@ -733,16 +732,11 @@ static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 		u32 len = pb[i].len;
 
 		memcpy(dest, (src + offset), len);
-		msg_size += len;
 		dest += len;
 	}
 
-	if (padding) {
+	if (padding)
 		memset(dest, 0, padding);
-		msg_size += padding;
-	}
-
-	return msg_size;
 }
 
 static inline int netvsc_send_pkt(