mbedtls_ssl_config min_tls_version, max_tls_version

Store the TLS version in tls_version instead of major, minor version num

Note: existing application use which accesses the struct member
(using MBEDTLS_PRIVATE) is not compatible on little-endian platforms,
but is compatible on big-endian platforms.  For systems supporting
only TLSv1.2, the underlying values are the same (=> 3).

New setter functions are more type-safe,
taking argument as enum mbedtls_ssl_protocol_version:
mbedtls_ssl_conf_max_tls_version()
mbedtls_ssl_conf_min_tls_version()

Signed-off-by: Glenn Strauss <gstrauss@gluelogic.com>
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 8053e76..c79fcfa 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -3541,7 +3541,7 @@
         return( MBEDTLS_ERR_SSL_INVALID_RECORD );
     }
 
-    if( minor_ver > ssl->conf->max_minor_ver )
+    if( minor_ver > ( ssl->conf->max_tls_version & 0xFF ) )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "minor version mismatch" ) );
         return( MBEDTLS_ERR_SSL_INVALID_RECORD );