[roll] Roll fuchsia [docs] Add documentation for boot time

Adds docs for the new boot timeline, as described by RFC-0260. Also
updates the monotonic time documentation to clarify that it does not
progress during periods of suspension.

Original-Bug: 328306129
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1129898
Original-Revision: d16f4f70c1bbd6d91afd8e24f0bb42e61ea56a8e
GitOrigin-RevId: ba08c09ff0806c7478f9274a941949df917ea514
Change-Id: Ibb905adc11550b56ba17b0f28d56abf346f970cc

Author: Anirudh Mathukumilli

stem

@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="6c273a0af006790834499cf915d2cffc40bc9df5"/>
+             revision="d16f4f70c1bbd6d91afd8e24f0bb42e61ea56a8e"/>
   </projects>
   <hooks>
     <hook name="install-environment"