Replace Tactility SystemEvents with new kernel implementation (#598)

TactilityKernel now has a system event API to replace the one from the Tactility subproject. It also implements several tests for it.

Tactility/Include/Tactility/SystemEvents.h

@@ -1,28 +0,0 @@
-#pragma once
-
-#include <cstdint>
-#include <functional>
-
-namespace tt::kernel {
-
-enum class SystemEvent {
-    BootSplash,
-    /** Gained IP address */
-    NetworkConnected,
-    NetworkDisconnected,
-    Time,
-};
-
-/** Value 0 mean "no subscription" */
-typedef uint32_t SystemEventSubscription;
-constexpr SystemEventSubscription NoSystemEventSubscription = 0U;
-
-typedef std::function<void(SystemEvent)> OnSystemEvent;
-
-void publishSystemEvent(SystemEvent event);
-
-SystemEventSubscription subscribeSystemEvent(SystemEvent event, OnSystemEvent handler);
-
-void unsubscribeSystemEvent(SystemEventSubscription subscription);
-
-}

Tactility/Include/Tactility/service/rtctime/RtcTimeService.h

@@ -1,21 +1,22 @@
 #pragma once
 
-#include <Tactility/SystemEvents.h>
 #include <Tactility/service/Service.h>
 
 #include <memory>
 
 struct Device;
+struct SystemEvent;
 
 namespace tt::service::rtctime {
 
 class RtcTimeService final : public Service {
 
-    kernel::SystemEventSubscription timeEventSubscription = 0;
+    bool timeEventSubscribed = false;
     Device* rtcDevice = nullptr;
 
     Device* findRtcDevice();
-    void onTimeChanged(kernel::SystemEvent event);
+    void onTimeChanged();
+    static void onTimeChangedTrampoline(struct SystemEvent* event, void* context);
 
 public: