Adjust comment describing mbedtls_ssl_set_hs_own_cert()

mbedtls_ssl_set_hs_own_cert() is callable from the certificate selection
callback.

Signed-off-by: Glenn Strauss <gstrauss@gluelogic.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index aa6a212..b819bba 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -3565,7 +3565,7 @@
  * \brief          Set own certificate and key for the current handshake
  *
  * \note           Same as \c mbedtls_ssl_conf_own_cert() but for use within
- *                 the SNI callback.
+ *                 the SNI callback or the certificate selection callback.
  *
  * \note           Passing null \c own_cert clears the certificate list for
  *                 the current handshake.
@@ -3585,7 +3585,7 @@
  *                 current handshake
  *
  * \note           Same as \c mbedtls_ssl_conf_ca_chain() but for use within
- *                 the SNI callback.
+ *                 the SNI callback or the certificate selection callback.
  *
  * \param ssl      SSL context
  * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
@@ -3599,7 +3599,7 @@
  * \brief          Set authmode for the current handshake.
  *
  * \note           Same as \c mbedtls_ssl_conf_authmode() but for use within
- *                 the SNI callback.
+ *                 the SNI callback or the certificate selection callback.
  *
  * \param ssl      SSL context
  * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or