msm: acpuclock-8064: add higher bus speed and use it for OC frequencies (v2)

The previous patch seems to be causing a little more heat.
https://github.com/mrg666/android_kernel_mako/commit/87e04e7f50bde7e56b1cea4b8f9a53c3172ce28e
This patch tries the same without continuously scaling the L2 frequency
- add 600 MHz bus speed
- add 1188 MHz L2 speed using the new bus speed
- use 1188 L2 speed for OC cpu frequencies