fsl_ddr: Move DDR config options to driver Kconfig

Create driver/ddr/fsl/Kconfig and move existing options. Clean up
existing macros.

Signed-off-by: York Sun <york.sun@nxp.com>
[trini: Migrate sbc8641d, xpedite537x and MPC8536DS, run a moveconfig.py -s]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/T1042RDB_PI_defconfig b/configs/T1042RDB_PI_defconfig
index 4a9bd3a..0eee7a5 100644
--- a/configs/T1042RDB_PI_defconfig
+++ b/configs/T1042RDB_PI_defconfig
@@ -21,6 +21,7 @@
 CONFIG_CMD_PING=y
 CONFIG_CMD_EXT2=y
 CONFIG_CMD_FAT=y
+CONFIG_SYS_FSL_DDR3=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_NETDEVICES=y