[S] Change in coreboot[master]: mb/google/myst: Enable eSPI SCI events

[Tim Van Patten (Code Review)]

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

Tim Van Patten has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74101 )

Change subject: mb/google/myst: Enable eSPI SCI events
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Patch Set 7:

(1 comment)

File src/mainboard/google/myst/ec.c:

https://review.coreboot.org/c/coreboot/+/74101/comment/bc5e43ad_ab978e49 
PS6, Line 14: GEVENT_3
> It does come from that sheet.

I'm probably missing it; can you point out where?
> This was errantly left in from Skyrim.  There isn't an event associated with the interrupt line on Myst.  I'm not sure if that's problematic.

Raul would probably know best, but I think we need this for the linux kernel to assign wake events to SCIs that come in (and make sure the correct wake counts are incremented, etc.). I'm not sure what's involved with getting one assigned though.