Add changelog entry for #3150: simplify ssl_write_certificate_request

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/ChangeLog.d/ssl_write_certificate_request.txt b/ChangeLog.d/ssl_write_certificate_request.txt
new file mode 100644
index 0000000..2d3067a
--- /dev/null
+++ b/ChangeLog.d/ssl_write_certificate_request.txt
@@ -0,0 +1,3 @@
+Changes
+   * Simplify a bounds check in ssl_write_certificate_request(). Contributed
+     by irwir in #3150.