apkverify: add ziputil

apkverify doesn't need all zip features. ziputil provides zip_sections()
to discover the layout of a zip file.

Bug: 190343842
Test: cargo test
Change-Id: Ib6354828cebe819fd3f48265089815ccf29f18ea
diff --git a/apkverify/src/lib.rs b/apkverify/src/lib.rs
index 9ea0e14..9930099 100644
--- a/apkverify/src/lib.rs
+++ b/apkverify/src/lib.rs
@@ -19,6 +19,7 @@
 mod bytes_ext;
 mod sigutil;
 mod v3;
+mod ziputil;
 
 use anyhow::Result;
 use std::path::Path;