gma: Consolidate Intel IGD ACPI code some more

Consolidate some common (and mostly broken) code. Will try to fix things
in separate commits.

Maybe, igd.asl taken from gm45 (the non-PCH case) could also be used for
i945 and sch. But this needs further investigation.

Change-Id: Id3663bf588458e1e71920b96a3149f96947921e9
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: http://review.coreboot.org/11702
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
Tested-by: build bot (Jenkins)
diff --git a/src/northbridge/intel/sandybridge/acpi/sandybridge.asl b/src/northbridge/intel/sandybridge/acpi/sandybridge.asl
index 742b0f1..5aafcc1 100644
--- a/src/northbridge/intel/sandybridge/acpi/sandybridge.asl
+++ b/src/northbridge/intel/sandybridge/acpi/sandybridge.asl
@@ -55,4 +55,4 @@
 }
 
 // Integrated graphics 0:2.0
-#include "igd.asl"
+#include <drivers/intel/gma/acpi/pch.asl>