Phanbell: Explicitly set buck voltages in SPL

* Bucks 1-4 will be reconfigured via DVS in the kernel.
* Buck 5 is explicitly set to 1.0V
* Regulator lock/unlock is added, this ensures that in warm or cold
reset the values will be set.

Change-Id: I8d8be74bddbbd081030fe1762b9f9c6534c7fb77
1 file changed