ARM: mm: proc-mohawk: add suspend resume for mohawk

When enable ARCH_SUSPEND_POSSIBLE, it need defintion of
cpu_mohawk_do_suspend and cpu_mohawk_do_resume

Signed-off-by: Chao Xie <chao.xie@marvell.com>
Signed-off-by: Haojian Zhuang <&lt;haojian.zhuang@gmail.com>