Migrate freeze test to Soong

Bug: 33691272
Test: m selinux_policy on sc-dev
Change-Id: Ie536d885034e5d888f1329ac189fd0bf9723a6c4
diff --git a/build/soong/Android.bp b/build/soong/Android.bp
index 2282112..3126430 100644
--- a/build/soong/Android.bp
+++ b/build/soong/Android.bp
@@ -38,6 +38,7 @@
         "policy.go",
         "selinux.go",
         "selinux_contexts.go",
+        "sepolicy_freeze.go",
         "sepolicy_vers.go",
         "versioned_policy.go",
     ],