NEWS: update doc for 5.0.2rc2

Change version and submodule hashes.

Signed-off-by: Wenduo Wang <[email protected]>

bot:notacherrypick

Author: wenduwan

docs/news/news-v5.0.x.rst

@@ -4,14 +4,20 @@ Open MPI v5.0.x series
 This file contains all the NEWS updates for the Open MPI v5.0.x
 series, in reverse chronological order.
 
-Open MPI version v5.0.2rc1
+Open MPI version v5.0.2rc2
 --------------------------
-:Date: 24 January 2024
+:Date: 31 January 2024
 
 - Internal PMIx and PRRTe versions:
 
-  - PMIx (v4.2.8-3-ge68bdfcf). Commit hash: ``e68bdfcf4133cb4c1af31c591bb1d26ed63fe911``.
-  - PRRTE (v3.0.3-5-g8bd181af08). Commit hash: ``8bd181af0836375e66c741c1c94364d8a44918e5``.
+  - PMIx (v4.2.8). Commit hash: ``d1c1ed0c2e64f19ad49291241a43630ea7fdce28``.
+  - PRRTE (v3.0.3). Commit hash: ``e383f5ad70c2633420d3425e9fb67e69b6bfd9c4``.
+
+  .. note:: 5.0.2rc2 has pinned PMIx and PRRTe to the respective previous
+            release tags. This effectively excludes the submodule updates
+            in rc1. This action is needed in order to ensure the internal
+            modules always refer to stable releases that can be matched by
+            external installations.
 
 - Bugfixes and changes (in chronological order)