Change in coreboot[master]: mb/intel/shadowmountain: Add the romstage code

[V Sowmya (Code Review)]

Attention is currently required from: Martin Roth, Tim Wawrzynczak, Balaji Manigandan, Aamir Bohra.
Hello build bot (Jenkins), Patrick Georgi, Martin Roth, Tim Wawrzynczak, Angel Pons, Subrata Banik, Balaji Manigandan, Aamir Bohra,

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

https://review.coreboot.org/c/coreboot/+/49731

to look at the new patch set (#2).

Change subject: mb/intel/shadowmountain: Add the romstage code
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mb/intel/shadowmountain: Add the romstage code

This patch includes the romstage changes for the
shadowmountain board.

BUG=b:175808146
TEST= Build and boot shadowmountain board till early ramstage.

Signed-off-by: V Sowmya 
Change-Id: Ifd0bbcea9d4916d82bb1e3c275dd79d97a79727a
---
M src/mainboard/intel/shadowmountain/Kconfig
M src/mainboard/intel/shadowmountain/Makefile.inc
A src/mainboard/intel/shadowmountain/romstage.c
A src/mainboard/intel/shadowmountain/spd/Makefile.inc
A src/mainboard/intel/shadowmountain/spd/shadowmountain_lp5.spd.hex
M src/mainboard/intel/shadowmountain/variants/baseboard/Makefile.inc
M src/mainboard/intel/shadowmountain/variants/baseboard/devicetree.cb
M src/mainboard/intel/shadowmountain/variants/baseboard/include/baseboard/variants.h
A src/mainboard/intel/shadowmountain/variants/baseboard/memory.c
9 files changed, 169 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/31/49731/2