Uniformize wording for removal of deprecated things

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index b5ad445..1666f8c 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -3188,7 +3188,7 @@
  * \warning        Use of RC4 in DTLS/TLS has been prohibited by RFC 7465
  *                 for security reasons. Use at your own risk.
  *
- * \note           This function is deprecated and will likely be removed in
+ * \note           This function is deprecated and will be removed in
  *                 a future version of the library.
  *                 RC4 is disabled by default at compile time and needs to be
  *                 actively enabled for use with legacy systems.