timer/sysclt: Restrict timer migration sysctl values to 0 and 1

timer/sysclt: Restrict timer migration sysctl values to 0 and 1

commit b94bf594cf8ed67cdd0439e70fa939783471597a upstream.

timer_migration sysctl acts as a boolean switch, so the allowed values
should be restricted to 0 and 1.

Add the necessary extra fields to the sysctl table entry to enforce that.

[ tglx: Rewrote changelog ]

Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Link: http://lkml.kernel.org/r/1492640690-3550-1-git-send-email-mhjungk@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kazuhiro Hayashi <kazuhiro3.hayashi@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>