ARM: dts: msm: Enable CPR hardware for msm8226

Enable the RB-CPR hardware found on MSM8226 targets so that the
application processor supply voltage may be scaled based upon
CPR hardware recommendations.  This results in power savings
because the processor supply voltage can be set to lower more
aggressive levels.

Change-Id: Ica805c866c1e088823e9f3a2b3c79c3dd8923ba1
Signed-off-by: David Collins <collinsd@codeaurora.org>