goruby.c: call Init_golf [ci skip]

* goruby.c (init_golf): call Init_golf, because ruby_init_ext only
  registers the function since r43514.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55993 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

goruby.c

@@ -20,7 +20,8 @@ RUBY_EXTERN void ruby_init_ext(const char *name, void (*init)(void));
 static VALUE
 init_golf(VALUE arg)
 {
-    ruby_init_ext("golf.so", Init_golf);
+    Init_golf();
+    rb_provide("golf.so");
     return arg;
 }