[roll] Roll fuchsia [dm-verity] Use hash_start_block to read leaf nodes from the hash device

Currently, the device mapper reads the leaf nodes of the merkle tree off
the end of the hash device. However, Android might add trailing metadata
to the end of the hash device. Instead, the device mapper should use
hash_start_block and then calculate the size of the merkle tree to
figure out which offset to read the leaf nodes from.

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1046613
Original-Revision: 916dfae31bbfe53ff49a3834809bdead06b1f475
GitOrigin-RevId: b9fef2a88265c02fb208adde3d0a105603f17e90
Change-Id: I02cbca4fef548c0ea22f351a9f77031a85ea5062
diff --git a/stem b/stem
index 3de6dba..df19044 100644
--- a/stem
+++ b/stem
@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="75d0cda1572f2c8764d1dbd0eb6e02a0af5dce69"/>
+             revision="916dfae31bbfe53ff49a3834809bdead06b1f475"/>
   </projects>
   <hooks>
     <hook name="install-environment"