via/epia-m: Switch to per-device ACPI

Change-Id: Ic63fc1f933fff5cd58adcd4299c4ac2a62c4bb68
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/6941
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>