Build Win32 resources as .res files and dump them into the .spec.c file.

diff --git a/libtest/hello3.spec b/libtest/hello3.spec
index 8dd4e4a..67b1097 100644
--- a/libtest/hello3.spec
+++ b/libtest/hello3.spec
@@ -2,4 +2,4 @@
 mode	guiexe
 type	win32
 init	WinMain
-rsrc	hello3res
+rsrc	hello3res.res