[M] Change in flashrom[master]: serial: Call set_custom_baudrate() thrice

[Peter Stuge (Code Review)]

Attention is currently required from: Thomas Heijligen.

Hello build bot (Jenkins), Thomas Heijligen,

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

https://review.coreboot.org/c/flashrom/+/70569

to look at the new patch set (#4).

Change subject: serial: Call set_custom_baudrate() thrice
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serial: Call set_custom_baudrate() thrice

Call the function before tcsetattr() settings are known, then again
with settings prepared but not yet applied and finally a third time
after tcsetattr().

Darwin support needs this change; there custom_baud code must be
called to modify the settings passed to tcsetattr() and then again
after tcsetattr() returns.

The change should be non-functional on all currently supported systems;
current code calls set_custom_baudrate() before any tcsetattr()
settings are prepared, so we have three stages in total.

This change originates from discussion of the macOS patch proposed by
Denis Ahrens in https://review.coreboot.org/c/flashrom/+/67822

Change-Id: I40cc443cfb7bf6b212b31826d437b898cc13c427
Signed-off-by: Peter Stuge 
---
M custom_baud.c
M custom_baud_linux.c
M include/custom_baud.h
M serial.c
4 files changed, 52 insertions(+), 6 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/69/70569/4