bsp/simulator: enable mouse motion track in SDL

Tested OK in RTGUI repo.
add libc in link when enable RT_USING_NEWLIB
Merge pull request #55 from grissiom/bsp-sim-enable-mouse-move

bsp/simulator: enable mouse motion track in SDL
Merge pull request #54 from weety/new-branch

Modify the interrupt interface implementations and changes some parameters definition
implement __rt_ffs in kernel service library
implement __rt_ffs for armv5