Revert "dtbhtool: Add LOCAL_MODULE_TAGS := optional"

Superflous commit, see:
http://source.android.com/source/add-device.html.

This reverts commit 7598a16084a6aa1f708bea3c6448f824f73db851.

Change-Id: I75af8b68b8dc07a27d1bc2bf23550f3c1c8ddb77
diff --git a/dtbhtool/libfdt/Android.mk b/dtbhtool/libfdt/Android.mk
index 7c19a05..8c62034 100644
--- a/dtbhtool/libfdt/Android.mk
+++ b/dtbhtool/libfdt/Android.mk
@@ -10,7 +10,6 @@
     fdt_wip.c
 
 LOCAL_MODULE := libfdt
-LOCAL_MODULE_TAGS := optional
 
 include $(BUILD_HOST_STATIC_LIBRARY)
 
@@ -24,6 +23,5 @@
     fdt_wip.c
 
 LOCAL_MODULE := libfdt
-LOCAL_MODULE_TAGS := optional
 
-include $(BUILD_STATIC_LIBRARY)
+include $(BUILD_STATIC_LIBRARY)
\ No newline at end of file