nxp: Migrate a number of DDR related symbols to Kconfig

- Guard most of the options in drivers/ddr/fsl/Kconfig with
  SYS_FSL_DDR || SYS_FSL_MMDC.
- Migrate FSL_DMA, DDR_ECC, DDR_ECC_CMD, and ECC_INIT_VIA_DDRCONTROLLER
  to Kconfig.
- Clean up the logic for including the DDR_ECC_CMD code.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/P5040DS_NAND_defconfig b/configs/P5040DS_NAND_defconfig
index d7ac3a9..3591d98 100644
--- a/configs/P5040DS_NAND_defconfig
+++ b/configs/P5040DS_NAND_defconfig
@@ -34,6 +34,8 @@
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_DM=y
 CONFIG_FSL_CAAM=y
+CONFIG_DDR_ECC=y
+CONFIG_ECC_INIT_VIA_DDRCONTROLLER=y
 CONFIG_DM_I2C=y
 CONFIG_I2C_SET_DEFAULT_BUS_NUM=y
 CONFIG_SYS_I2C_FSL=y