ARM: dts: msm: add cti dt entry for save and restore

Add dt entry for save and restore of CPU CTIs as these CTIs do not
retain state on L2 SCU rail collapse.

Change-Id: I05db01d7c9bde77f49235d7daaeb5366eb389515
Signed-off-by: Pan Fang <fangpan@codeaurora.org>