simulator: move SDL setting staff into drivers/SConstruct

This could not only make a cleaner SConstruct, but could also benefit
RTGUI building.

bsp/simulator/SConstruct

@@ -84,13 +84,6 @@ else:
 
 objs = PrepareBuilding(env, RTT_ROOT, has_libcpu=False, remove_components=['rtgui'])
 if GetDepend('RT_USING_RTGUI'):
-    sdl_lib = ['SDL', 'SDLmain']
-    sdl_lib_path = [os.path.abspath('SDL/lib/x86')]
-    sdl_include_path = [os.path.abspath('SDL/include')]
-    env.Append(LIBS=sdl_lib)
-    env.Append(LIBPATH=sdl_lib_path)
-    env.Append(CPPPATH=sdl_include_path)
-
     if RTT_RTGUI:
         objs += SConscript(os.path.join(RTT_RTGUI, 'SConscript'),
 						   variant_dir='build/components/rtgui',