slip: remove redundant NULL-pointer check before calling slhc_free

Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/slip.c

@@ -194,7 +194,6 @@ static int sl_alloc_bufs(struct slip *sl, int mtu)
 err_exit:
 #ifdef SL_INCLUDE_CSLIP
 	kfree(cbuff);
-	if (slcomp)
 	slhc_free(slcomp);
 #endif
 	kfree(xbuff);