Change in coreboot[master]: mb/google/brask: add the mkbp device

[Paul Menzel (Code Review)]

Attention is currently required from: Tim Wawrzynczak, Zhuohao Lee.
Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58744 )

Change subject: mb/google/brask: add the mkbp device
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Patch Set 1:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/58744/comment/7d05d197_c8fc4e77 
PS1, Line 9: In order to let the ec passing the key event
           : like recovery and power key to the OS, we need
           : to include EC_ENABLE_MKBP_DEVICE to generate
           : the MKBP device.
           : 
           : BUG=b:204519353, b:204512547
           : BRANCH=None
           : TEST=pressed recovery key and power button in
           :      the OS and checked the UI behavior
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