Change in coreboot[master]: libpayload: i8042: Enable keyboard translation by defualt on exit

[Nico Huber (Code Review)]

Attention is currently required from: Duncan Laurie, Tim Wawrzynczak.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52737 )

Change subject: libpayload: i8042: Enable keyboard translation by defualt on exit
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Patch Set 1: Code-Review+2

(3 comments)

Patchset:

PS1: 
Thanks for the patch and testing!

I was able to verify the `default y` on a Thinkpad X201 with a
FILO payload (modified to call keyboard_disconnect(), WIP). As
expected, stock Linux reports an "AT Translated Set 2 keyboard"
(instead of "AT Raw Set 2 keyboard"). All keys confirmed working
individually, usual combinations work as well.

File payloads/libpayload/Kconfig:

https://review.coreboot.org/c/coreboot/+/52737/comment/cde5949d_40b1b95f 
PS1, Line 388: PC_KEYBOARD_TRANSLATION
Maybe we can squeeze a `HANDOVER` into the name? e.g.

config PC_KEYBOARD_HANDOVER_TRANSLATED

because it only affects the exit path.

https://review.coreboot.org/c/coreboot/+/52737/comment/7f3cf8e8_1a95828b 
PS1, Line 389: in
I'm not 100% sure how to parse this. With translation enabled, the
controller is translating _from_ set 2 (_(in)to_ set 1).