This patch adds a way to configure PLL frequencies. The configuration is
given by board logic.
These values should only be modified by the bootloader, but we don't have
that yet so the flag is never activated.
Adds board definition for imx93-evk board
- Support for the Cortex-A55 core in i.MX93, support for the Cortex-M33
core is _not_ provided
- "nsh" profile is provided, this includes a minimalistic feature set
which boots the SoM to nsh console
- A bootloader is required, u-boot has been tested
