Stop using deprecated interfaces

Use `Kaleidoscope.useLoopHook` instead of `loop_hook_use` (which is getting
deprecated).

Signed-off-by: Gergely Nagy <kaleidoscope@gergo.csillger.hu>

src/Kaleidoscope-Model01-TestMode.cpp

@@ -25,7 +25,7 @@ void TestMode_::begin(void) {
   white.r = 160;
   white.g = 160;
   white.b = 160;
-  loop_hook_use(this->loopHook);
+  Kaleidoscope.useLoopHook(this->loopHook);
 }
 
 void TestMode_::loopHook(bool postClear) {