ARM: dts: msm: Scale cache with CPUfreq using devfreq governor and device

For SoCs with asynchronous cache:
- Add qcom,cache device to provide the clock and the list of usable
  frequencies to the devfreq clock driver. Also set the default governor
  for this device to "cpufreq".
- Add CPUfreq to cache freq mapping for the cache device.
- Enable the DEVFREQ_SIMPLE_DEV config for these targets.

Change-Id: I5bda30420e79935d8d660306dd25d45042a3945b
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>