Get rid of dependency on core from linux build (2/2)

When building bluetooth stack for linux, don't include
dependencies from core.
diff --git a/include/hardware/hardware.h b/include/hardware/hardware.h
index bf076f6..5ba37e9 100644
--- a/include/hardware/hardware.h
+++ b/include/hardware/hardware.h
@@ -20,8 +20,10 @@
 #include <stdint.h>
 #include <sys/cdefs.h>
 
+#ifndef _HW_DONT_INCLUDE_CORE_
 #include <cutils/native_handle.h>
 #include <system/graphics.h>
+#endif // _HW_DONT_INCLUDE_CORE_
 
 __BEGIN_DECLS