nb/intel: Deduplicate vbt header

Move header and delete duplicates.

Change-Id: I0e1f5d9082626062f95afe718f6ec62a68f0d828
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/18903
Tested-by: build bot (Jenkins)
Tested-by: coreboot org <coreboot.org@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/common/opregion.c

@@ -17,7 +17,7 @@
 #include <string.h>
 #include <cbmem.h>
 
-#include "gma.h"
+#include <drivers/intel/gma/opregion.h>
 #include "opregion.h"
 #include "vbt.h"