runtime: generate Go defs for C types.

R=rsc, mattn
CC=golang-dev
https://golang.org/cl/4047047
diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index 462ac6f..54ae5c0 100644
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -63,7 +63,7 @@
 typedef	struct	Type		Type;
 typedef	struct	Defer		Defer;
 typedef	struct	Panic		Panic;
-typedef	struct	hash		Hmap;
+typedef	struct	Hmap		Hmap;
 typedef	struct	Hchan		Hchan;
 typedef	struct	Complex64	Complex64;
 typedef	struct	Complex128	Complex128;