Create driver/ddr/fsl/Kconfig and move existing options. Clean up
existing macros.
Signed-off-by: NYork Sun <york.sun@nxp.com>
[trini: Migrate sbc8641d, xpedite537x and MPC8536DS, run a moveconfig.py -s]
Signed-off-by: NTom Rini <trini@konsulko.com>