Work around bug in the SPI driver

This makes the IMU start and restart reliably.

Also remove the gyro to avoid having to coordinate with that thread.

Change-Id: I0645a4b47f76c479bf479629c8c8ad5c6dab98ef
diff --git a/y2016/wpilib_interface.cc b/y2016/wpilib_interface.cc
index 9bf2b0e..2f37bcb 100644
--- a/y2016/wpilib_interface.cc
+++ b/y2016/wpilib_interface.cc
@@ -724,6 +724,7 @@
     reader.set_dma(make_unique<DMA>());
     ::std::thread reader_thread(::std::ref(reader));
 
+    // TODO(Brian): This interacts poorly with the SpiRxClearer in ADIS16448.
     ::frc971::wpilib::GyroSender gyro_sender;
     ::std::thread gyro_thread(::std::ref(gyro_sender));