[roll] Roll fuchsia [zbi] Only compute CRC32 if the flag is set in the header

This matches the behavior prior to 47bf3dc and eliminates the error
message during the build.

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/395920
Original-Revision: 5578bfa7bfc9ec752d20385a75cdc587f6f06576
GitOrigin-RevId: 9ac8b77e60cc748dd3d6eac32a17b2dc99122008
Change-Id: I4efa8b1e90b8d667ca796c3cbf2dddeebd7175c9
diff --git a/stem b/stem
index 2e829e6..e98570d 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="a6e2fad92f598d5e00e57ae74bbb1c1c40c4775f"/>
+             revision="5578bfa7bfc9ec752d20385a75cdc587f6f06576"/>
   </projects>
   <hooks>
     <hook name="install-fx"