drivers: ddr: imx8mp: Add inline ECC feature support

drivers: ddr: imx8mp: Add inline ECC feature support

the DRAM Controller in i.MX8MP will support a feature called "Inline ECC".
This is supported for all 3 supported DRAM technologies (LPDDR4, DDR4 and
DDR3L). When this feature is enabled by software, the DRAM Controller
reserves 12.5% of DRAM capacity for ECC information, and presents only
the non-ECC portion (lower 87.5% of the installed capacity of DRAM) to
the rest of the SoC.
The DRAM memory can be divided into 8 regions so that if a use case only
requires ECC protection on a subset of memory, then only that subset of
memory need support inline ECC. If this occurs, then there is no
performance penalty accessing the non-ECC-protected memory (no need to
access ECC for this portion of the memory map). This is all configured
with the DRAM Controller.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>