Drop libdexfile from host prebuilts.

After the removal of libdexfile_external it's in the SDK rather an
internal dependency.

Test: `m nothing` with new prebuilt drop into prebuilts/module_sdk/art
Bug: 143978909
Change-Id: Ieeba81066253dc1a5ac922f88e97525ef02bc4f5
diff --git a/build/sdk/Android.bp b/build/sdk/Android.bp
index 1e3e15e..429424d 100644
--- a/build/sdk/Android.bp
+++ b/build/sdk/Android.bp
@@ -215,7 +215,6 @@
                 "profman",
             ],
             native_libs: [
-                "libdexfile", // libdexfile_external dependency
                 "libartpalette", // libdexfile dependency
                 "libartbase", // libdexfile dependency
             ],