Bring PowerDistributionPanel in ahal up-to-date

The previous code wasn't working with 2020 WPILib/images. Not that we
really rely on this code, but it's good to keep it working.

Change-Id: I2b5e013f71181119db41c09482183c4cbb708f2f
diff --git a/frc971/wpilib/ahal/PowerDistributionPanel.h b/frc971/wpilib/ahal/PowerDistributionPanel.h
index fcb14ed..dc80158 100644
--- a/frc971/wpilib/ahal/PowerDistributionPanel.h
+++ b/frc971/wpilib/ahal/PowerDistributionPanel.h
@@ -10,6 +10,8 @@
 #include <memory>
 #include <string>
 
+#include <hal/Types.h>
+
 #include "frc971/wpilib/ahal/SensorBase.h"
 
 namespace frc {
@@ -33,7 +35,7 @@
   void ClearStickyFaults();
 
  private:
-  int m_module;
+  hal::Handle<HAL_PDPHandle> m_handle;
 };
 
 }  // namespace frc