net: wangxun: use net_prefetch to simplify logic

Use net_prefetch to remove #ifdef and simplify prefetch logic. This
follows the pattern introduced in a previous commit f468f21b ("net:
Take common prefetch code structure into a function"), which replaced
the same logic in all existing drivers at that time.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Link: https://patch.msgid.link/20240729152651.258713-1-jdamato@fastly.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/wangxun/libwx/wx_lib.c

@@ -251,10 +251,7 @@ static struct sk_buff *wx_build_skb(struct wx_ring *rx_ring,
 				  rx_buffer->page_offset;
 
 		/* prefetch first cache line of first page */
-		prefetch(page_addr);
-#if L1_CACHE_BYTES < 128
-		prefetch(page_addr + L1_CACHE_BYTES);
-#endif
+		net_prefetch(page_addr);
 
 		/* allocate a skb to store the frags */
 		skb = napi_alloc_skb(&rx_ring->q_vector->napi, WX_RXBUFFER_256);