Add ChangeLog.d/new-mbedtls_x509_crt_parse_der_with_ext_cb_routine.txt

Signed-off-by: Nicola Di Lieto <nicola.dilieto@gmail.com>
diff --git a/ChangeLog.d/new-mbedtls_x509_crt_parse_der_with_ext_cb_routine.txt b/ChangeLog.d/new-mbedtls_x509_crt_parse_der_with_ext_cb_routine.txt
new file mode 100644
index 0000000..fdea746
--- /dev/null
+++ b/ChangeLog.d/new-mbedtls_x509_crt_parse_der_with_ext_cb_routine.txt
@@ -0,0 +1,5 @@
+Features
+   * Add new mbedtls_x509_crt_parse_der_with_ext_cb() routine which allows
+     parsing unsupported certificate extensions via user provided callback.
+     Contributed by Nicola Di Lieto <nicola.dilieto@gmail.com> in #3243 as
+     a solution to #3241.