Remote key export identifier used for TLS < 1.2.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index bf8a9e2..540f552 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -961,7 +961,6 @@
 typedef enum
 {
    MBEDTLS_SSL_TLS_PRF_NONE,
-   MBEDTLS_SSL_TLS_PRF_TLS1,
    MBEDTLS_SSL_TLS_PRF_SHA384,
    MBEDTLS_SSL_TLS_PRF_SHA256,
    MBEDTLS_SSL_HKDF_EXPAND_SHA384,