keyboard: wrong defined macro for WIN32
keyboard: wrong defined macro for WIN32

On windows client, there's no effect for guest when
enabling CAPS_LOCK/NUM_LOCK/SCROLL_LOCK on
(because of the delay, guest may take the effect for several seconds).
There's a wrong defined macro, then <modifiers> is ALWAYS 0,
and the keyboard state of guest is synchronized with the state client
by spice_gtk_session_sync_keyboard_modifiers_for_channel(...).

freedesktop-unofficial-mirror/spice__spice-gtk,elmarco/spice-gtk,Fantu/spice-gtk,Fantu/spice-gtk,guodong/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,elmarco/spice-gtk,SPICE/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,SPICE/spice-gtk,guodong/spice-gtk,Fantu/spice-gtk,flexVDI/spice-gtk,fgouget/spice-gtk,elmarco/spice-gtk,Fantu/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,elmarco/spice-gtk,fgouget/spice-gtk,SPICE/spice-gtk,flexVDI/spice-gtk,guodong/spice-gtk,guodong/spice-gtk,SPICE/spice-gtk,fgouget/spice-gtk