fd_set used by this header is supposed to be defined in sys/select.h and not
including this header resulted in compilation problems under QNX. And
including sys/time.h shouldn't hurt and is needed by select() under many
systems anyhow.
See #11817.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@63716 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775