net: unexport skb_gro_receive()

skb_gro_receive() used to be used by SCTP, it is no longer the case.

skb_gro_receive_list() is in the same category : never used from modules.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/skbuff.c

@@ -3727,7 +3727,6 @@ int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(skb_gro_receive_list);
 
 /**
  *	skb_segment - Perform protocol segmentation on skb.
@@ -4191,7 +4190,6 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb)
 	NAPI_GRO_CB(skb)->same_flow = 1;
 	return 0;
 }
-EXPORT_SYMBOL_GPL(skb_gro_receive);
 
 #ifdef CONFIG_SKB_EXTENSIONS
 #define SKB_EXT_ALIGN_VALUE	8