sched: Remove unneeded __ref tag

Those two functions no longer call alloc_bootmmem_cpumask_var(),
so no need to tag them with __init_refok.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <4A35DD5B.9050106@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>