includes: Add video mixing renderer header.
diff --git a/include/Makefile.in b/include/Makefile.in
index f2b4af9..3b6370a 100644
--- a/include/Makefile.in
+++ b/include/Makefile.in
@@ -399,6 +399,7 @@
 	ver.h \
 	vfw.h \
 	vfwmsgs.h \
+	vmrender.idl \
 	wfext.h \
 	winbase.h \
 	wincon.h \