Enable overclocking in the standard configuration without undervolt.
-   Set the default frequency at 1566MHz in the standard configuration
 for uniform frequency increments
-   Add 1674 and 1728 MHz steps for overclocking
-   Enable user voltage interface in the standard configuration.
-   Rename MACH_APQ8064_OC option as MACH_APQ8064_UV to indicate the
 alternative undervolt configuration