Change in coreboot[master]: drivers/ipmi: implement "POST complete" notification functionality

[Michael Niewöhner (Code Review)]

Hello build bot (Jenkins),

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

https://review.coreboot.org/c/coreboot/+/48096

to look at the new patch set (#28).

Change subject: drivers/ipmi: implement "POST complete" notification functionality
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drivers/ipmi: implement "POST complete" notification functionality

Some server boards like OPC Tiogapass or Supermicro X11SSM-F use a gpio
for signalling "POST complete" to BMC/IPMI. Add a new driver devicetree
option to set the gpio and configure a callback that pulls the gpio low
right before jumping to the payload.

Test: Check that sensor readings appear in BMC web interface when the
payload gets executed. Successfully tested on Supermicro X11SSM-F with
CB:48097 applied.

Signed-off-by: Michael Niewöhner 
Change-Id: I34764858be9c7f7f1110ce885fa056591164f148
---
M src/drivers/ipmi/chip.h
M src/drivers/ipmi/ipmi_kcs_ops.c
2 files changed, 33 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/96/48096/28