ah: Don't return NET_XMIT_DROP on input.

When the ahash driver returns -EBUSY, AH4/6 input functions return
NET_XMIT_DROP, presumably copied from the output code path.  But
returning transmit codes on input doesn't make a lot of sense.
Since NET_XMIT_DROP is a positive int, this gets interpreted as
the next header type (i.e., success).  As that can only end badly,
remove the check.
Signed-off-by: NNick Bowler <nbowler@elliptictech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/ah4.c

@@ -369,8 +369,6 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
 		if (err == -EINPROGRESS)
 			goto out;
 
-		if (err == -EBUSY)
-			err = NET_XMIT_DROP;
 		goto out_free;
 	}
 

net/ipv6/ah6.c

@@ -581,8 +581,6 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
 		if (err == -EINPROGRESS)
 			goto out;
 
-		if (err == -EBUSY)
-			err = NET_XMIT_DROP;
 		goto out_free;
 	}