We have several boards that use the same ICS307 CLK chip to drive the
System clock and DDR clock. Move the code into a common location so we
share it.
Convert the P2020DS board as the first to use the new common ICS307
code.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Timur Tabi <timur@freescale.com>