Add merge_zips (go_binary) to prebuilts.

Similar to zip2zip and soong_zip, this allows Bazel to use go_binary prebuilts without the go toolchain.

Test: N/A
Change-Id: Id61f5fa2ccc5ecaf38294d1a5d329f42601524b3
diff --git a/build-prebuilts.sh b/build-prebuilts.sh
index dafa8e3..5550c51 100755
--- a/build-prebuilts.sh
+++ b/build-prebuilts.sh
@@ -96,6 +96,7 @@
         hidl-lint
         m4
         make
+        merge_zips
         ninja
         one-true-awk
         openssl