fixed a printf format width in the indexer code
diff --git a/frc971/control_loops/index/index.cc b/frc971/control_loops/index/index.cc
index 72597c6..fd9b612 100644
--- a/frc971/control_loops/index/index.cc
+++ b/frc971/control_loops/index/index.cc
@@ -753,7 +753,7 @@
case Goal::INTAKE:
safe_goal_ = Goal::READY_SHOOTER;
safe_to_change_state = false;
- LOG(INFO, "We have %d discs, time to preload automatically\n",
+ LOG(INFO, "We have %"PRId32" discs, time to preload automatically\n",
hopper_disc_count_);
break;
case Goal::READY_SHOOTER: