southbridge/intel: Move `i82801gx/acpi/platform.asl` to `common/acpi`

Commit 24813c14 (i945: Consolidate acpi/platform.asl) creates the file
in the directory `src/southbridge/intel/i82801gx/acpi`. Devices with the
southbridge `intel/i82801ix`, like the laptop Lenovo X200, use the exact
same ASL code though. So share this in the directory
`src/southbridge/intel/common/acpi`.

Change-Id: I33b7993bcdbef7233ed85a683b2858ac72c1d642
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/11881
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
diff --git a/src/mainboard/intel/d945gclf/dsdt.asl b/src/mainboard/intel/d945gclf/dsdt.asl
index 8cd9c14..4a0525b 100644
--- a/src/mainboard/intel/d945gclf/dsdt.asl
+++ b/src/mainboard/intel/d945gclf/dsdt.asl
@@ -31,7 +31,7 @@
 
 	// global NVS and variables
 	#include <southbridge/intel/i82801gx/acpi/globalnvs.asl>
-	#include <southbridge/intel/i82801gx/acpi/platform.asl>
+	#include <southbridge/intel/common/acpi/platform.asl>
 
 	// General Purpose Events
 	//#include "acpi/gpe.asl"