[M] Change in coreboot[main]: mb/google/dedede/var/boxy: Wait up for 3s for HPD ready signal

[Joey Peng (Code Review)]

Attention is currently required from: Derek Huang, Joey Peng.

Hello Derek Huang, build bot (Jenkins),

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

https://review.coreboot.org/c/coreboot/+/78146?usp=email

to look at the new patch set (#7).

Change subject: mb/google/dedede/var/boxy: Wait up for 3s for HPD ready signal
......................................................................

mb/google/dedede/var/boxy: Wait up for 3s for HPD ready signal

Boxy project needs to wait for HPD ready to continue boot in ramstage to
avoid no display in DEV screen and recovery screen.

BUG=b:303346324
TEST=Both type-c ports can display in DEV screen and recovery screen

Signed-off-by: Joey Peng 
Change-Id: I208fdf8234886b2ef43a4b972e6682892238e8e9
---
M src/mainboard/google/dedede/mainboard.c
M src/mainboard/google/dedede/variants/baseboard/include/baseboard/variants.h
M src/mainboard/google/dedede/variants/boxy/ramstage.c
3 files changed, 52 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/46/78146/7