general: Use deducation guides for std::lock_guard and std::unique_lock

Since C++17, the introduction of deduction guides for locking facilities
means that we no longer need to hardcode the mutex type into the locks
themselves, making it easier to switch mutex types, should it ever be
necessary in the future.

src/input_common/udp/client.cpp

@@ -165,7 +165,7 @@ void Client::OnPadData(Response::PadData data) {
     Common::Vec3f accel = Common::MakeVec<float>(-data.accel.x, data.accel.y, -data.accel.z);
     Common::Vec3f gyro = Common::MakeVec<float>(-data.gyro.pitch, -data.gyro.yaw, data.gyro.roll);
     {
-        std::lock_guard<std::mutex> guard(status->update_mutex);
+        std::lock_guard guard(status->update_mutex);
 
         status->motion_status = {accel, gyro};