sh: Fix build alloc_thread_info_node function

By commit b6a84016

,
alloc_thread_info was replaced by alloc_thread_info_node.
However, the change of the function name and the addition of the argument
were incomplete.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>