Rename MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL to MBEDTLS_SSL_PROTO_TLS1_3

As we have now a minimal viable implementation of TLS 1.3,
let's remove EXPERIMENTAL from the config option enabling
it.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/ssl_ciphersuites.c b/library/ssl_ciphersuites.c
index b10a963..62588dc 100644
--- a/library/ssl_ciphersuites.c
+++ b/library/ssl_ciphersuites.c
@@ -52,14 +52,14 @@
 #if defined(MBEDTLS_SSL_CIPHERSUITES)
     MBEDTLS_SSL_CIPHERSUITES,
 #else
-#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
     /* TLS 1.3 ciphersuites */
     MBEDTLS_TLS1_3_AES_128_GCM_SHA256,
     MBEDTLS_TLS1_3_AES_256_GCM_SHA384,
     MBEDTLS_TLS1_3_CHACHA20_POLY1305_SHA256,
     MBEDTLS_TLS1_3_AES_128_CCM_SHA256,
     MBEDTLS_TLS1_3_AES_128_CCM_8_SHA256,
-#endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
 
     /* Chacha-Poly ephemeral suites */
     MBEDTLS_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
@@ -292,7 +292,7 @@
 
 static const mbedtls_ssl_ciphersuite_t ciphersuite_definitions[] =
 {
-#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
 #if defined(MBEDTLS_AES_C)
 #if defined(MBEDTLS_GCM_C)
 #if defined(MBEDTLS_SHA384_C)
@@ -336,7 +336,7 @@
       MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_4,
       0 },
 #endif /* MBEDTLS_CHACHAPOLY_C && MBEDTLS_SHA256_C */
-#endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
 
 #if defined(MBEDTLS_CHACHAPOLY_C) && \
     defined(MBEDTLS_SHA256_C) && \