Fix function name in comment for asio::placeholders::iterator.

asio/include/asio/placeholders.hpp

diff --git a/asio/include/asio/placeholders.hpp b/asio/include/asio/placeholders.hpp
index 6fda487..bd177fc 100644
--- a/asio/include/asio/placeholders.hpp
+++ b/asio/include/asio/placeholders.hpp
@@ -38,7 +38,7 @@
 
 /// An argument placeholder, for use with boost::bind(), that corresponds to
 /// the iterator argument of a handler for asynchronous functions such as
-/// asio::basic_resolver::resolve.
+/// asio::basic_resolver::async_resolve.
 unspecified iterator;
 
 #elif defined(__BORLANDC__) || defined(__GNUC__)