Add custom pm sysmodule

sysmodules/pm/source/my_thread.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <3ds/types.h>
+#include <3ds/result.h>
+#include <3ds/svc.h>
+#include <3ds/synchronization.h>
+
+#define THREAD_STACK_SIZE 0x1000
+
+typedef struct MyThread {
+    Handle handle;
+    void *p;
+    void (*ep)(void *p);
+    bool finished;
+    void* stacktop;
+} MyThread;
+
+Result MyThread_Create(MyThread *t, void (*entrypoint)(void *p), void *p, void *stack, u32 stackSize, int prio, int affinity);
+Result MyThread_Join(MyThread *thread, s64 timeout_ns);
+void MyThread_Exit(void);