Change in coreboot[master]: mb/intel/shadowmountain: Add the ASL code

[V Sowmya (Code Review)]

Attention is currently required from: Paul Menzel, Tim Wawrzynczak, Balaji Manigandan, Aamir Bohra.
V Sowmya has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49733 )

Change subject: mb/intel/shadowmountain: Add the ASL code
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Patch Set 3:

(3 comments)

File src/mainboard/intel/shadowmountain/dsdt.asl:

https://review.coreboot.org/c/coreboot/+/49733/comment/de031ea6_9305b21c 
PS3, Line 19: // global NVS and variables
> /* */

Done

https://review.coreboot.org/c/coreboot/+/49733/comment/535580b5_c24bb63a 
PS3, Line 22: // CPU
> /* */

Done

https://review.coreboot.org/c/coreboot/+/49733/comment/890ca790_5d411789 
PS3, Line 34: // Chrome OS Embedded Controller
> /* */

Done