tls13: nst early_data: remove duplicate code

Signed-off-by: Yanray Wang <yanray.wang@arm.com>
diff --git a/library/ssl_tls13_client.c b/library/ssl_tls13_client.c
index 361f0c0..c9680c2 100644
--- a/library/ssl_tls13_client.c
+++ b/library/ssl_tls13_client.c
@@ -2663,12 +2663,6 @@
                                               const unsigned char *end)
 {
     MBEDTLS_SSL_CHK_BUF_READ_PTR(buf, end, 4);
-    if ((end - buf) != 4) {
-        MBEDTLS_SSL_PEND_FATAL_ALERT(
-            MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR,
-            MBEDTLS_ERR_SSL_DECODE_ERROR);
-        return MBEDTLS_ERR_SSL_DECODE_ERROR;
-    }
 
     if (ssl->session != NULL) {
         ssl->session->max_early_data_size = MBEDTLS_GET_UINT32_BE(buf, 0);