kernel/smp.c: remove cpumask_ipi

kernel/smp.c: remove cpumask_ipi

After 9a46ad6 ("smp: make smp_call_function_many() use logic similar to
smp_call_function_single()"), cfd->cpumask is accessed only in
smp_call_function_many().  So there is no more need to copy it into
cfd->cpumask_ipi before putting csd into the list.  The cpumask_ipi field
is obsolete and can be removed.

Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Wang YanQing <udknight@gmail.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>