[DOC] Update Object#=~ [ci skip]

see r65989

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66420 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

object.c

@@ -1678,9 +1678,10 @@ rb_false(VALUE obj)
  *  call-seq:
  *     obj =~ other  -> nil
  *
- *  Pattern Match---Overridden by descendants (notably
+ * This method is deprecated.
- *  <code>Regexp</code> and <code>String</code>) to provide meaningful
+ *
- *  pattern-match semantics.
+ * This is not only unuseful but also troublesome because it
+ * may hide a type error.
  */
 
 static VALUE