The first and only parameter of sl_alloc() is unused, so remove it.
Fixes: 5342b77c4123 slip: ("Clean up create and destroy") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>