Document more precisely what goes into the default preset

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index fe33ac8..a8376a2 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -2237,7 +2237,7 @@
 #if defined(MBEDTLS_ECP_C)
 /**
  * \brief          Set the allowed curves in order of preference.
- *                 (Default: all defined curves.)
+ *                 (Default: all defined curves in order of decreasing size.)
  *
  *                 On server: this only affects selection of the ECDHE curve;
  *                 the curves used for ECDH and ECDSA are determined by the
@@ -2269,7 +2269,7 @@
 #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 /**
  * \brief          Set the allowed hashes for signatures during the handshake.
- *                 (Default: all available hashes except MD5.)
+ *                 (Default: all SHA2 hashes, largest first.)
  *
  * \note           This only affects which hashes are offered and can be used
  *                 for signatures during the handshake. Hashes for message