NFC: Convert to Chrono

Author: kjbracey

features/nfc/source/nfc/NFCController.cpp

@@ -20,6 +20,8 @@
 
 #include "stack/transceiver/transceiver.h"
 
+using std::milli;
+using namespace std::chrono;
 using namespace mbed;
 using namespace mbed::nfc;
 
@@ -181,12 +183,9 @@ void NFCController::scheduler_process(bool hw_interrupt)
     _timeout.detach(); // Cancel timeout - if it triggers, it's ok as we'll have an "early" iteration which will likely be a no-op
 
     // Process stack events
-    uint32_t timeout_ms = nfc_scheduler_iteration(_scheduler, hw_interrupt ? EVENT_HW_INTERRUPT : EVENT_NONE);
+    duration<uint32_t, milli> timeout{nfc_scheduler_iteration(_scheduler, hw_interrupt ? EVENT_HW_INTERRUPT : EVENT_NONE)};
 
-    _timeout.attach_us(
-        callback(this, &NFCController::on_timeout),
-        timeout_ms * (us_timestamp_t) 1000
-    );
+    _timeout.attach(callback(this, &NFCController::on_timeout), timeout);
 }
 
 void NFCController::on_hw_interrupt()