Add missing frees to generate nonce test

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index bb4d7e6..819c61b 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -3782,6 +3782,8 @@
 
 exit:
     psa_destroy_key( key );
+    mbedtls_free( output_data );
+    mbedtls_free( final_data );
     psa_aead_abort( &operation );
     PSA_DONE( );
 }