Change in coreboot[master]: console: Allow disabling compiled in slow coreboot consoles

[Patrick Georgi (Code Review)]

Hello build bot (Jenkins), Greg Edelston, Julius Werner, Angel Pons, Dossym Nurmukhanov,

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

https://review.coreboot.org/c/coreboot/+/45208

to look at the new patch set (#5).

Change subject: console: Allow disabling compiled in slow coreboot consoles
......................................................................

console: Allow disabling compiled in slow coreboot consoles

Allow disabling slow consoles such as the serial output by adding a
file "disable-slow-consoles" to CBFS.

This allows using an image for both deployment and testing scenarios
with only the CBFS entry modified to toggle (the typically slow)
serial console.

This feature is hidden behind a default-off Kconfig flag and is also
transparent in that a lack of the file keeps all consoles enabled
like before.

BUG=b:151346403
BRANCH=none
TEST=Taking a Chrome OS config for google/eve, it behaves as expected
with no entry present and both entry states with negligible performance
loss.

Change-Id: I4f1f5c45e5ea889176d04e0db438ca2aa7c536ee
Signed-off-by: Patrick Georgi 
---
M src/console/Kconfig
M src/console/init.c
2 files changed, 37 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/08/45208/5