literals.rdoc: fix typos

* doc/syntax/literals.rdoc (Strings): fix typos.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51872 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

doc/syntax/literals.rdoc

@@ -133,13 +133,13 @@ Basically only one character can be placed after <tt>?</tt>:
   ?abc #=> SyntaxError
 
 Exceptionally, <tt>\C-</tt>, <tt>\M-</tt> and their combination are allowed
-before a character.  They means "control", "meta" and "control-meta"
+before a character.  They mean "control", "meta" and "control-meta"
 respectively:
 
   ?\C-a    #=> "\x01"
   ?\M-a    #=> "\xE1"
   ?\M-\C-a #=> "\x81"
-  ?\C-\A-a #=> "\x81", same as above
+  ?\C-\M-a #=> "\x81", same as above
 
 === Here Documents