[S] Change in coreboot[master]: mb/google/myst: Add smihandler

[Eric Lai (Code Review)]

Attention is currently required from: Raul Rangel, Jon Murphy, Mark Hasemeyer.

Eric Lai has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74100 )

Change subject: mb/google/myst: Add smihandler
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Patch Set 19:

(3 comments)

File src/mainboard/google/myst/variants/baseboard/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/74100/comment/0ac2d9f0_1834331b 
PS19, Line 5: smm-y += gpio.c
no need here since you remove the table.

File src/mainboard/google/myst/variants/baseboard/smihandler.c:

https://review.coreboot.org/c/coreboot/+/74100/comment/fcaf5409_785b2d96 
PS19, Line 4: #include <console/console.h>
not used here.

https://review.coreboot.org/c/coreboot/+/74100/comment/fc01ce12_31146a74 
PS19, Line 8: #include <gpio.h>
not used here.