dp83640: reverse arguments to list_add_tail

dp83640: reverse arguments to list_add_tail

In this code, it appears that phyter_clocks is a list head, based on
the previous list_for_each, and that clock->list is intended to be a
list element, given that it has just been initialized in
dp83640_clock_init.  Accordingly, switch the arguments to
list_add_tail, which takes the list head as the second argument.

Fixes: cb646e2b02b27 ("ptp: Added a clock driver for the National Semiconductor PHYTER.")
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>