Add missing newline

Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
diff --git a/ChangeLog.d/zeroising_of_plaintext_buffer.txt b/ChangeLog.d/zeroising_of_plaintext_buffer.txt
index d7dee29..f618beb 100644
--- a/ChangeLog.d/zeroising_of_plaintext_buffer.txt
+++ b/ChangeLog.d/zeroising_of_plaintext_buffer.txt
@@ -1,4 +1,4 @@
 Security
    * Zeroising of plaintext buffers in mbedtls_ssl_read() to erase unused
      application data from memory. Reported in #689 by
-     Johan Uppman Bruce of Sectra.
\ No newline at end of file
+     Johan Uppman Bruce of Sectra.