Import gx, PadClamp, rest of mtx, TRK 2.6 and MSL (#525)

* Match mtx and Padclamp.c

* Match the rest of GX

* Import TRK 2.6

* Import MSL headers and files

* Merge some MSL headers into ours

src/TRK_MINNOW_DOLPHIN/mainloop.c

@@ -0,0 +1,70 @@
+#include "TRK_MINNOW_DOLPHIN/MetroTRK/Portable/serpoll.h"
+#include "TRK_MINNOW_DOLPHIN/MetroTRK/Portable/msgbuf.h"
+#include "TRK_MINNOW_DOLPHIN/MetroTRK/Portable/dispatch.h"
+#include "TRK_MINNOW_DOLPHIN/Os/dolphin/targcont.h"
+#include "TRK_MINNOW_DOLPHIN/ppc/Generic/targimpl.h"
+
+void TRKHandleRequestEvent(TRKEvent* event)
+{
+	TRKBuffer* buffer = TRKGetBuffer(event->msgBufID);
+	TRKDispatchMessage(buffer);
+}
+
+void TRKHandleSupportEvent(TRKEvent* event) { TRKTargetSupportRequest(); }
+
+void TRKIdle()
+{
+	if (TRKTargetStopped() == FALSE) {
+		TRKTargetContinue();
+	}
+}
+
+void TRKNubMainLoop(void)
+{
+	void* msg;
+	TRKEvent event;
+	BOOL isShutdownRequested;
+	BOOL isNewInput;
+
+	isShutdownRequested = FALSE;
+	isNewInput          = FALSE;
+	while (isShutdownRequested == FALSE) {
+		if (TRKGetNextEvent(&event) != FALSE) {
+			isNewInput = FALSE;
+
+			switch (event.eventType) {
+			case NUBEVENT_Null:
+				break;
+
+			case NUBEVENT_Request:
+				TRKHandleRequestEvent(&event);
+				break;
+
+			case NUBEVENT_Shutdown:
+				isShutdownRequested = TRUE;
+				break;
+
+			case NUBEVENT_Breakpoint:
+			case NUBEVENT_Exception:
+				TRKTargetInterrupt(&event);
+				break;
+
+			case NUBEVENT_Support:
+				TRKHandleSupportEvent(&event);
+				break;
+			}
+
+			TRKDestructEvent(&event);
+			continue;
+		}
+
+		if ((isNewInput == FALSE) || (*(u8*)gTRKInputPendingPtr != '\0')) {
+			isNewInput = TRUE;
+			TRKGetInput();
+			continue;
+		}
+
+		TRKIdle();
+		isNewInput = FALSE;
+	}
+}