Change in coreboot[master]: soc/mediatek: Add early_init for passing data across stages

[Jianjun Wang (Code Review)]

Attention is currently required from: Hung-Te Lin, Paul Menzel, Rex-BC Chen, Angel Pons, Yu-Ping Wu.
Hello Hung-Te Lin, build bot (Jenkins), Rex-BC Chen, Paul Menzel, Angel Pons, Yu-Ping Wu,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/63019

to look at the new patch set (#10).

Change subject: soc/mediatek: Add early_init for passing data across stages
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soc/mediatek: Add early_init for passing data across stages

Add support for "early_init_data" region, which can be used to store
data initialized in an early stage (such as bootblock), and retrieve it
in later stages (such as ramstage).

TEST=Build pass and boot up to kernel successfully via SSD on Dojo
board, here is the SSD information in boot log:
 == NVME IDENTIFY CONTROLLER DATA ==
    PCI VID   : 0x15b7
    PCI SSVID : 0x15b7
    SN        : 21517J440114
    MN        : WDC PC SN530 SDBPTPZ-256G-1006
    RAB       : 0x4
    AERL      : 0x7
    SQES      : 0x66
    CQES      : 0x44
    NN        : 0x1
Identified NVMe model WDC PC SN530 SDBPTPZ-256G-1006

BUG=b:178565024
BRANCH=cherry

Signed-off-by: Jianjun Wang 
Change-Id: I01f91b7fe2cbe4f73b5c616bb7aae778dee27d9a
---
A src/soc/mediatek/common/early_init.c
A src/soc/mediatek/common/include/soc/early_init.h
2 files changed, 78 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/19/63019/10