ARM: dts: msm: Add the CCI clock to the 8939 pm node

Allow idle driver to enable/disable the CCI clock during
RPM assisted power collapse. Each core count towards as
one enable vote for the CCI clock.

Change-Id: Id904cccc461bba05b7df89122117031a39150c43
Signed-off-by: Venkat Devarasetty <vdevaras@codeaurora.org>