[Kernel/APT] Stub some APT and threading stuff to make OoT go further

src/core/kernel/threads.cpp

@@ -115,4 +115,11 @@ void Kernel::getThreadID() {
 
 	regs[0] = SVCResult::Success;
 	regs[1] = thread->getData<Thread>()->index;
+}
+
+void Kernel::releaseMutex() {
+	const Handle handle = regs[0];
+
+	logSVC("ReleaseMutex (handle = %x) (STUBBED)\n", handle);
+	regs[0] = SVCResult::Success;
 }