Use libcutils_headers for android_filesystem_config.h

android_filesystem_config.h is found since system/core/include is on
the include path for all projects and contains a symlink to the real
android_filesystem_config.h.  This is fragile and the below bug seeks
to remove this symlink and have users correctly depend on
libcutils_headers.

Bug: 165825252
Test: build
Change-Id: I1aad6a2e8fbe87635e97b0ac1be3414403353382
diff --git a/libcutils/Android.bp b/libcutils/Android.bp
index 04b8f66..524b715 100644
--- a/libcutils/Android.bp
+++ b/libcutils/Android.bp
@@ -28,6 +28,7 @@
     name: "libcutils_headers",
     vendor_available: true,
     recovery_available: true,
+    ramdisk_available: true,
     host_supported: true,
     apex_available: [
         "//apex_available:platform",