Distribute missing header

(cherry picked from commit ac795f1a)
Signed-off-by: Pierre Ynard <linkfanel@yahoo.fr>

src/Makefile.am

@@ -124,6 +124,7 @@ noinst_HEADERS = \
 	../include/vlc_update.h \
 	../include/vlc_vod.h \
 	../include/vlc_vout_wrapper.h \
+	../include/vlc_windows_interfaces.h \
 	$(NULL)
 
 ../include/vlc_about.h: Makefile.am $(top_srcdir)/COPYING $(top_srcdir)/THANKS $(top_srcdir)/AUTHORS