net: rename CONFIG_NET_LL_RX_POLL to CONFIG_NET_RX_BUSY_POLL

Eliezer renames several *ll_poll to *busy_poll, but forgets
CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too.

Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 3df4d4c..2c3d0f5 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -740,7 +740,7 @@
 
 	skb_copy_secmark(new, old);
 
-#ifdef CONFIG_NET_LL_RX_POLL
+#ifdef CONFIG_NET_RX_BUSY_POLL
 	new->napi_id	= old->napi_id;
 #endif
 }