fixed mavericks compile problem, return iterator of _map.end() instead of iterator of NULL
fixed mavericks compile problem, return iterator of _map.end() instead of iterator of NULL

libimobiledevice/libplist,libimobiledevice/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,Tatsh/libplist,Tatsh/libplist,libimobiledevice/libplist,libimobiledevice-win32/libplist,libimobiledevice-win32/libplist