Add LuaJIT CMake for Android build

libs/LuaJIT/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.6)
+
+project(LuaJIT LANGUAGES C)
+
+if(ANDROID)
+	add_library(luajit STATIC IMPORTED GLOBAL)
+	set_target_properties(luajit PROPERTIES
+		IMPORTED_LOCATION android/${ANDROID_ABI}/libluajit.a
+		INCLUDE_DIRECTORIES src
+	)
+else()
+	message(WARNING "This script is only for Android")
+endif()