Changelog entry for removal of the RSA-PSK key exchange

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/ChangeLog.d/tls-key-exchange-rsa.txt b/ChangeLog.d/tls-key-exchange-rsa.txt
new file mode 100644
index 0000000..4df6b3e
--- /dev/null
+++ b/ChangeLog.d/tls-key-exchange-rsa.txt
@@ -0,0 +1,2 @@
+Removals
+   * Remove support for the RSA-PSK key exchange in TLS 1.2.