Fixed building on Linux.

src/osi/src/run.cpp

 #include <osi/run.hpp>
 #include <osi/simulator.hpp>
 #include <utils/assumptions.hpp>
+#include <utils/config.hpp>
 #include <SDL2/SDL.h>
 #include <glad/glad.h>
 #include <imgui.h>
-#include <imgui_impl_sdl.h>
+#if PLATFORM() == PLATFORM_WINDOWS()
+#   include <imgui_impl_sdl.h>
+#else
+#   include <imgui_impl_sdl2.h>
+#endif
 #include <imgui_impl_opengl3.h>
 #include <chrono>
 #include <algorithm>