Remove NDK exports

Base headers should come from sysroot.

Bug: N/A
Test: build
Change-Id: Ifd6d6353851a16c2744af241c6092657c595223c
diff --git a/libsync/Android.bp b/libsync/Android.bp
index b6b4a6e..99c88cf 100644
--- a/libsync/Android.bp
+++ b/libsync/Android.bp
@@ -27,9 +27,6 @@
     name: "libsync",
     symbol_file: "libsync.map.txt",
     first_version: "26",
-    export_header_libs: [
-        "libsync_headers",
-    ],
 }
 
 cc_defaults {