Declare get_write_protect_state() without ChromeOS

Change-Id: I72471ac68088cd26f8277b27b75b7d44ad72cfc4
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5642
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-by: Aaron Durbin <adurbin@google.com>

src/mainboard/intel/baskingridge/chromeos.c

@@ -18,7 +18,7 @@
  */
 
 #include <string.h>
-#include <vendorcode/google/chromeos/chromeos.h>
+#include <bootmode.h>
 #include <arch/io.h>
 #include <device/device.h>
 #include <device/pci.h>