core+daemon: eliminate scheduler::{schedule,cancel} wrappers

Also move core/global-io.hpp to daemon/global.hpp

Refs: #4528, #4883
Change-Id: I0b99029f1a19d7451aab57099cd3303b7eb42ff3
diff --git a/daemon/fw/asf-strategy.cpp b/daemon/fw/asf-strategy.cpp
index 779daee..46acaf4 100644
--- a/daemon/fw/asf-strategy.cpp
+++ b/daemon/fw/asf-strategy.cpp
@@ -26,6 +26,7 @@
 #include "asf-strategy.hpp"
 #include "algorithm.hpp"
 #include "core/logger.hpp"
+#include "daemon/global.hpp"
 
 namespace nfd {
 namespace fw {
@@ -226,9 +227,8 @@
     NFD_LOG_TRACE("Scheduling timeout for " << fibEntry.getPrefix() << " to: " << egress
                   << " in " << time::duration_cast<time::milliseconds>(timeout) << " ms");
 
-    scheduler::EventId id = scheduler::schedule(timeout,
-        bind(&AsfStrategy::onTimeout, this, interest.getName(), egress.face.getId()));
-
+    auto id = getScheduler().schedule(timeout, bind(&AsfStrategy::onTimeout, this,
+                                                    interest.getName(), egress.face.getId()));
     faceInfo.setTimeoutEvent(id, interest.getName());
   }
 }