Fix compatibility with Boost 1.70.

Adapted for 14.2.5 from these upstream commits:
https://github.com/ceph/ceph/commit/064f142746ae97f54865069cdacf5aae2b1b14f6
https://github.com/ceph/ceph/commit/f1651b8c509d60787d10c4115e29fecfd2da237c

diff --git a/src/rgw/rgw_asio_frontend.cc b/src/rgw/rgw_asio_frontend.cc
--- a/src/rgw/rgw_asio_frontend.cc
+++ b/src/rgw/rgw_asio_frontend.cc
@@ -83,7 +83,8 @@
 using SharedMutex = ceph::async::SharedMutex<boost::asio::io_context::executor_type>;
 
 template <typename Stream>
-void handle_connection(RGWProcessEnv& env, Stream& stream,
+void handle_connection(boost::asio::io_context& context,
+		       RGWProcessEnv& env, Stream& stream,
                        parse_buffer& buffer, bool is_ssl,
                        SharedMutex& pause_mutex,
                        rgw::dmclock::Scheduler *scheduler,
@@ -160,7 +161,7 @@
                                   rgw::io::add_conlen_controlling(
                                     &real_client))));
       RGWRestfulIO client(cct, &real_client_io);
-      auto y = optional_yield{socket.get_io_context(), yield};
+      auto y = optional_yield{context, yield};
       process_request(env.store, env.rest, &req, env.uri_prefix,
                       *env.auth_registry, &client, env.olog, y, scheduler);
     }
@@ -604,7 +605,7 @@
           return;
         }
         buffer->consume(bytes);
-        handle_connection(env, stream, *buffer, true, pause_mutex,
+        handle_connection(context, env, stream, *buffer, true, pause_mutex,
                           scheduler.get(), ec, yield);
         if (!ec) {
           // ssl shutdown (ignoring errors)
@@ -622,7 +623,7 @@
         auto c = connections.add(conn);
         auto buffer = std::make_unique<parse_buffer>();
         boost::system::error_code ec;
-        handle_connection(env, s, *buffer, false, pause_mutex,
+        handle_connection(context, env, s, *buffer, false, pause_mutex,
                           scheduler.get(), ec, yield);
         s.shutdown(tcp::socket::shutdown_both, ec);
       });
diff --git a/src/rgw/rgw_dmclock_async_scheduler.h b/src/rgw/rgw_dmclock_async_scheduler.h
--- a/src/rgw/rgw_dmclock_async_scheduler.h
+++ b/src/rgw/rgw_dmclock_async_scheduler.h
@@ -82,7 +82,12 @@ class AsyncScheduler : public md_config_obs_t, public Scheduler {
   using Completion = async::Completion<Signature, async::AsBase<Request>>;
 
   using Clock = ceph::coarse_real_clock;
+#if BOOST_VERSION < 107000
   using Timer = boost::asio::basic_waitable_timer<Clock>;
+#else
+  using Timer = boost::asio::basic_waitable_timer<Clock,
+        boost::asio::wait_traits<Clock>, executor_type>;
+#endif
   Timer timer; //< timer for the next scheduled request
 
   CephContext *const cct;
diff --git a/src/rgw/rgw_reshard.h b/src/rgw/rgw_reshard.h
--- a/src/rgw/rgw_reshard.h
+++ b/src/rgw/rgw_reshard.h
@@ -183,7 +183,14 @@ class RGWReshardWait {
   ceph::condition_variable cond;
 
   struct Waiter : boost::intrusive::list_base_hook<> {
-    boost::asio::basic_waitable_timer<Clock> timer;
+#if BOOST_VERSION < 107000
+    using Timer = boost::asio::basic_waitable_timer<Clock>;
+#else
+    using Executor = boost::asio::io_context::executor_type;
+    using Timer = boost::asio::basic_waitable_timer<Clock,
+          boost::asio::wait_traits<Clock>, Executor>;
+#endif
+    Timer timer;
     explicit Waiter(boost::asio::io_context& ioc) : timer(ioc) {}
   };
   boost::intrusive::list<Waiter> waiters;