fw: Add pre loaded flash app and flash data storage

- Add per app flash storage
  - Adds four data areas. An app can allocate an area. Once allocated
    the area is tied to the CDI of the app and can only be
    read/written/deallocated by the same app.
- Add two pre loaded app slots to flash
  - Load an app from the first slot at boot. The app digest must match a
    specific digest specified in firmware.
  - Optionally load an app from the second slot
- Add a resetinfo area in FW_RAM which is used to signal an app's intent
  of resetting the system and, optionally, pass data to firmware or the
  next app in a bootchain.

Co-authored-by: Jonas Thörnblad <jonas@tillitis.se>
Co-authored-by: Mikael Ågren <mikael@tillitis.se>
Co-authored-by: Daniel Jobson <jobson@tillitis.se>

hw/application_fpga/fw/tk1/rng.h

@@ -0,0 +1,11 @@
+// Copyright (C) 2024 - Tillitis AB
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef RNG_H
+#define RNG_H
+
+#include <stdint.h>
+
+uint32_t rng_get_word(void);
+uint32_t rng_xorwow(uint32_t state, uint32_t acc);
+
+#endif