Drop dependency on IrrCompileConfig

The only remaining thing is IRRLICHT_SDK_VERSION via irrlicht.h

src/client/clientlauncher.cpp

@@ -553,13 +553,9 @@ void ClientLauncher::main_menu(MainMenuData *menudata)
 	m_rendering_engine->get_raw_device()->getCursorControl()->setVisible(true);
 
 	// Set absolute mouse mode
-#if IRRLICHT_VERSION_MT_REVISION >= 9
 	m_rendering_engine->get_raw_device()->getCursorControl()->setRelativeMode(false);
 #endif
 
-#endif
-
-
 	/* show main menu */
 	GUIEngine mymenu(&input->joystick, guiroot, m_rendering_engine, &g_menumgr, menudata, *kill);
 

src/client/game.cpp

@@ -2549,7 +2549,7 @@ void Game::checkZoomEnabled()
 
 void Game::updateCameraDirection(CameraOrientation *cam, float dtime)
 {
-#if !defined(__ANDROID__) && IRRLICHT_VERSION_MT_REVISION >= 9
+#ifndef __ANDROID__
 	if (isMenuActive())
 		device->getCursorControl()->setRelativeMode(false);
 	else

src/client/tile.cpp

@@ -21,7 +21,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #include <algorithm>
 #include <ICameraSceneNode.h>
-#include <IrrCompileConfig.h>
 #include "util/string.h"
 #include "util/container.h"
 #include "util/thread.h"