input_common, common: Add a few functions

These functions include reloading udp client, testing communication and configuring calibration. I also added a function to common/thread.h to use WaitFor.

src/input_common/udp/udp.cpp

@@ -85,6 +85,11 @@ State::~State() {
     Input::UnregisterFactory<Input::MotionDevice>("cemuhookudp");
 }
 
+void State::ReloadUDPClient() {
+    client->ReloadSocket(Settings::values.udp_input_address, Settings::values.udp_input_port,
+                         Settings::values.udp_pad_index);
+}
+
 std::unique_ptr<State> Init() {
     return std::make_unique<State>();
 }