[roll] Roll fuchsia [display][fidl] Add overview documentation.

This CL brings the display driver stack FIDL libraries in compliance
with the "Library Overview" section of the FIDL Style Guide.

Original-Bug: 316631158
Test: fx build (documentation-only change)
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1170874
Original-Revision: d4bb15c9a41c60055f5e7a29f0afa3581c98f66f
GitOrigin-RevId: cdd5eb295f905ed4fd7596a924f0ad3ce0e7cfa8
Change-Id: I70a2b2f7fb5fe470d865b3e79cd4b287e841e0b4

Author: Victor Costan

stem

@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="229d9ad171777a3202ace0ff3f02b1cc60e9fba7"/>
+             revision="d4bb15c9a41c60055f5e7a29f0afa3581c98f66f"/>
   </projects>
   <hooks>
     <hook name="install-environment"