ruby.h: fix typo

* include/ruby/ruby.h (ruby_check_sizeof_long_long): fix typo of
  availablity macro.  [ruby-dev:47341]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40739 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

include/ruby/ruby.h

@@ -103,7 +103,7 @@ typedef unsigned LONG_LONG ID;
 
 typedef char ruby_check_sizeof_int[SIZEOF_INT == sizeof(int) ? 1 : -1];
 typedef char ruby_check_sizeof_long[SIZEOF_LONG == sizeof(long) ? 1 : -1];
-#ifdef SIZEOF_LONG_LONG
+#ifdef HAVE_LONG_LONG
 typedef char ruby_check_sizeof_long_long[SIZEOF_LONG_LONG == sizeof(LONG_LONG) ? 1 : -1];
 #endif
 typedef char ruby_check_sizeof_voidp[SIZEOF_VOIDP == sizeof(void*) ? 1 : -1];