Remove additional references to sig_algs_heap_allocated

Signed-off-by: Ben Taylor <ben.taylor@linaro.org>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 5f4d31c..f7d7d9d 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -4379,9 +4379,6 @@
 
 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
-    if (ssl->handshake->sig_algs_heap_allocated) {
-        mbedtls_free((void *) handshake->sig_algs);
-    }
     handshake->sig_algs = NULL;
 #endif /* MBEDTLS_DEPRECATED_REMOVED */
 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)