crypto-client: reorganize source files/folders

The goal is to keep psasim as simple as possible:

- do not build a separate lib for psa-ff; build those source
  files as part of server or client
- do not have lot of different makefiles: just 1 that does all
  we need
- do not have several subfolders for headers: only 1 is enough
  for this kind of project

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/tests/psa-client-server/psasim/include/util.h b/tests/psa-client-server/psasim/include/util.h
new file mode 100644
index 0000000..558149f
--- /dev/null
+++ b/tests/psa-client-server/psasim/include/util.h
@@ -0,0 +1,33 @@
+/* Common definitions used for clients and services */
+
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#include "service.h"
+
+#define PRINT(fmt, ...) \
+    fprintf(stdout, fmt "\n", ##__VA_ARGS__)
+
+#if defined(DEBUG)
+#define INFO(fmt, ...) \
+    fprintf(stdout, "Info (%s - %d): " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__)
+
+#define ERROR(fmt, ...) \
+    fprintf(stdout, "Error (%s - %d): " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__)
+
+#define FATAL(fmt, ...) \
+    { \
+        fprintf(stdout, "Fatal (%s - %d): " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__); \
+        abort(); \
+    }
+#else /* DEBUG */
+#define INFO(...)
+#define ERROR(...)
+#define FATAL(...)
+#endif /* DEBUG*/
+
+#define PROJECT_ID              'M'
+#define PATHNAMESIZE            256
+#define TMP_FILE_BASE_PATH      "./"