Driver tested with LS1046A CPU. Driver designed to work with
other QorIQ family devices, however it was not tested with them.
Drivers for specific CPUs still need to provide configuration information.
Some of the QorIQ clockgen family functionality is not supported (e.g. Core
cluster B PLLs).
Driver supports coreclk and sysclk clock sources. PLL nodes are implemented
as read only and cannot be set.
This is a preparation patch for adding LS1046A clockgen support.