[roll] Roll fuchsia [hwreg][spmi] Support for SpmiRegisterArray

Also fix `WriteTo` type and endianness.

Original-Bug: b/374113073

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1149572
Original-Revision: 12c39b4c2755b9b093e0bc5da642206df870e5d2
GitOrigin-RevId: f9edd2fe8a136042dd9d9cece9797d1c43f3cc66
Change-Id: I4228c8a7b2332fb1fe202d9f9d8fa12fab91dc8f

Author: Ruby Zhuang

stem

@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="721029d3e496f33b721f6e4c0ed9388951438bcb"/>
+             revision="12c39b4c2755b9b093e0bc5da642206df870e5d2"/>
   </projects>
   <hooks>
     <hook name="install-environment"