acpi/: add missing license header

These were mostly written as part of the coreboot project, so get
the standard coreboot license header.

Change-Id: Ief13339647d3172e65bb18e6dcb54312a5c9472e
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/12917
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
1 file changed