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/ls2080aqds_qspi_defconfig b/configs/ls2080aqds_qspi_defconfig
index 0e92ad4..803d3bb 100644
--- a/configs/ls2080aqds_qspi_defconfig
+++ b/configs/ls2080aqds_qspi_defconfig
@@ -5,7 +5,7 @@
 CONFIG_FIT_VERBOSE=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_OF_STDOUT_VIA_ALIAS=y
-CONFIG_SYS_EXTRA_OPTIONS="SYS_FSL_DDR4,QSPI_BOOT,LS2080A"
+CONFIG_SYS_EXTRA_OPTIONS="QSPI_BOOT,LS2080A"
 CONFIG_QSPI_BOOT=y
 CONFIG_BOOTDELAY=10
 CONFIG_CMD_GREPENV=y