cpuset: remove unused task_has_mempolicy()

This is a remnant of commit 5f155f27cb7f ("mm, cpuset: always use
seqlock when changing task's nodemask").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
1 file changed