Created a kinetis MCG versioning scheme pulled in by Kinetis chip.h

   The motvations is to version the IP blocks of the Kinetis
   K series family of parts.

   This added versioning and configuration features for the
   Kinetis MCG IP block.

   It is envisioned that in the long term as a chip is added.
   The author of the new chip definitions will either find
   the exact configuration in an existing  chip define and
   add the new chip to it Or add the MCG feature configuration
   #defines to the chip ifdef list in
   arch/arm/include/kinetis/kinetis_mcg.h  In either case the
   author should mark it as "Verified to Document Number:"
   taken from the reference manual.

   The version KINETIS_MCG_VERSION_UKN has been applied to
   most all the SoCs in the kinetis arch prior to this commit.

   The exceptions are the CONFIG_ARCH_CHIP_MK60FN1M0VLQ12,
   All K64 and K66 which not have Verified MCG configurations.