tests: ssl: Free write/read test buffers

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index c1622e3..c381860 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -4523,6 +4523,8 @@
     mbedtls_test_init_handshake_options(&client_options);
     mbedtls_test_init_handshake_options(&server_options);
     mbedtls_ssl_session_init(&saved_session);
+    PSA_INIT();
+
     TEST_CALLOC(buf_write, write_size);
 
     /*
@@ -4532,8 +4534,6 @@
     read_size = (write_size / 2) + 1;
     TEST_CALLOC(buf_read, read_size);
 
-    PSA_INIT();
-
     /*
      * Run first handshake to get a ticket from the server.
      */
@@ -4714,6 +4714,8 @@
     mbedtls_test_free_handshake_options(&client_options);
     mbedtls_test_free_handshake_options(&server_options);
     mbedtls_ssl_session_free(&saved_session);
+    mbedtls_free(buf_write);
+    mbedtls_free(buf_read);
     mbedtls_debug_set_threshold(0);
     PSA_DONE();
 }