hp/pavilion_m6_1035dx: Add EC keyboard controller to devicetree

This causes coreboot to call the keyboard initialization code for the
KBC. This is only needed for payloads which do not initialize the
keyboard.

Change-Id: Id0bb77f2a8115fafc0cd6165a8431a7e07f0fac1
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/5514
Tested-by: build bot (Jenkins)
Reviewed-by: Idwer Vollering <vidwer@gmail.com>