net: emaclite: Remove custom BUFFER_ALIGN macro

BUFFER_ALIGN macro is used to calculate the number of bytes
required for the next alignment. Instead of this, we can directly
use the skb_reserve(skb, NET_IP_ALIGN) to make the protocol header
buffer aligned on at least a 4-byte boundary, where the NET_IP_ALIGN
is by default defined as 2. So removing the BUFFER_ALIGN and its
related defines which it can be done by the skb_reserve() itself.
Signed-off-by: NShravya Kumbham <shravya.kumbham@xilinx.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>

drivers/net/ethernet/xilinx/xilinx_emaclite.c

@@ -91,10 +91,6 @@
 #define XEL_HEADER_IP_LENGTH_OFFSET	16	/* IP Length Offset */
 
 #define TX_TIMEOUT		(60 * HZ)	/* Tx timeout is 60 seconds. */
-#define ALIGNMENT		4
-
-/* BUFFER_ALIGN(adr) calculates the number of bytes to the next alignment. */
-#define BUFFER_ALIGN(adr) ((ALIGNMENT - ((ulong)adr)) % ALIGNMENT)
 
 #ifdef __BIG_ENDIAN
 #define xemaclite_readl		ioread32be
@@ -596,7 +592,7 @@ static void xemaclite_rx_handler(struct net_device *dev)
 	u32 len;
 
 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
-	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
+	skb = netdev_alloc_skb(dev, len + NET_IP_ALIGN);
 	if (!skb) {
 		/* Couldn't get memory. */
 		dev->stats.rx_dropped++;
@@ -604,16 +600,7 @@ static void xemaclite_rx_handler(struct net_device *dev)
 		return;
 	}
 
-	/* A new skb should have the data halfword aligned, but this code is
-	 * here just in case that isn't true. Calculate how many
-	 * bytes we should reserve to get the data to start on a word
-	 * boundary
-	 */
-	align = BUFFER_ALIGN(skb->data);
-	if (align)
-		skb_reserve(skb, align);
-
-	skb_reserve(skb, 2);
+	skb_reserve(skb, NET_IP_ALIGN);
 
 	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);