ARM: mvebu: a38x: sync ddr training code with upstream

This syncs drivers/ddr/marvell/a38x/ with the mv_ddr-armada-17.10 branch
of https://github.com/MarvellEmbeddedProcessors/mv-ddr-marvell.git.

The upstream code is incorporated omitting the ddr4 and apn806 and
folding the nested a38x directory up one level. After that a
semi-automated step is used to drop unused features with unifdef

find drivers/ddr/marvell/a38x/ -name '*.[ch]' | \
xargs unifdef -m -UMV_DDR -UMV_DDR_ATF -UCONFIG_DDR4 \
-UCONFIG_APN806 -UCONFIG_MC_STATIC \
-UCONFIG_MC_STATIC_PRINT -UCONFIG_PHY_STATIC \
-UCONFIG_64BIT

INTER_REGS_BASE is updated to be defined as SOC_REGS_PHY_BASE.

Some now empty files are removed and the ternary license is replaced
with a SPDX GPL-2.0+ identifier.

Signed-off-by: Chris Packham <judge.packham@gmail.com>
Signed-off-by: Stefan Roese <sr@denx.de>

SPDX: Convert all of our single license tags to Linux Kernel style

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

arm: mvebu: Add Armada 38x DDR3 training code from Marvell bin_hdr

This patch adds the DDR3 setup and training code taken from the Marvell
U-Boot repository. This code used to be included as a binary (bin_hdr)
into the Armada A38x boot image. Not linked with the main U-Boot. With this
code addition and the serdes/PHY setup code, the Armada A38x support
in mainline U-Boot is finally self-contained. So the complete image
for booting can be built from mainline U-Boot. Without any additional
external inclusion.

Note:
This code has undergone many hours (days!) of coding-style cleanup and
refactoring. It still is not checkpatch clean though, I'm afraid. As the
factoring of the code has so many levels of indentation that many lines
are longer than 80 chars.

Signed-off-by: Stefan Roese <sr@denx.de>