fix warnings

Fix a couple warnings so we can use meson warning level 3.  Instances of
the following warnings are found and resolved:

  Wreorder
  Wsign-compare

Change-Id: Ia223b42aa6bf743cfa0e7042cc3d5a18977459be
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/TachSensor.cpp b/src/TachSensor.cpp
index 86b548f..91a08c1 100644
--- a/src/TachSensor.cpp
+++ b/src/TachSensor.cpp
@@ -50,9 +50,10 @@
                        const std::pair<size_t, size_t>& limits) :
     Sensor(boost::replace_all_copy(fanName, " ", "_"), std::move(_thresholds),
            sensorConfiguration, objectType, limits.second, limits.first),
-    path(path), objServer(objectServer), presence(std::move(presenceSensor)),
-    redundancy(redundancy), inputDev(io, open(path.c_str(), O_RDONLY)),
-    waitTimer(io), errCount(0)
+    objServer(objectServer), redundancy(redundancy),
+    presence(std::move(presenceSensor)),
+    inputDev(io, open(path.c_str(), O_RDONLY)), waitTimer(io), path(path),
+    errCount(0)
 {
     sensorInterface = objectServer.add_interface(
         "/xyz/openbmc_project/sensors/fan_tach/" + name,