Merge pull request #8940 from paul-elliott-arm/add_fixes_to_threading_changelog

Add issues fixed to threading MVP changelog entry
diff --git a/ChangeLog.d/add_threading_changelog.txt b/ChangeLog.d/add_threading_changelog.txt
index b6c79f0..e9f6cc7 100644
--- a/ChangeLog.d/add_threading_changelog.txt
+++ b/ChangeLog.d/add_threading_changelog.txt
@@ -4,3 +4,4 @@
      concurrently calling psa_crypto_init() when MBEDTLS_THREADING_C and
      MBEDTLS_THREADING_PTHREAD are defined. See
      docs/architecture/psa-thread-safety/psa-thread-safety.md for more details.
+     Resolves issues #3263 and #7945.