Implement clang-tidy fixes

clang-tidy allows the CI robot to check many things via static analysis.

All changes here were made by the clang-tidy robot, and include a number
of modernization fixes.  updating the tidy file will be done at a later
date.

Signed-off-by: Ed Tanous <etanous@nvidia.com>
Change-Id: I98cc4d600a3c589675507958f6d2350b2141216b
diff --git a/test/pid_zone_unittest.cpp b/test/pid_zone_unittest.cpp
index e4e7a26..37fb0fa 100644
--- a/test/pid_zone_unittest.cpp
+++ b/test/pid_zone_unittest.cpp
@@ -92,7 +92,7 @@
 {
   protected:
     PidZoneTest() :
-        property_index(), properties(), sdbus_mock_passive(), sdbus_mock_host(),
+        properties(), sdbus_mock_passive(), sdbus_mock_host(),
         sdbus_mock_mode(), sdbus_mock_enable()
     {
         EXPECT_CALL(sdbus_mock_host,
@@ -122,7 +122,7 @@
     }
 
     // unused
-    double property_index;
+    double property_index{};
     std::vector<std::string> properties;
     double propertyenable_index;
     std::vector<std::string> propertiesenable;
@@ -322,7 +322,7 @@
 
     std::map<std::string, std::pair<std::string, double>> failSensorList =
         zone->getFailSafeSensors();
-    EXPECT_EQ(1, failSensorList.size());
+    EXPECT_EQ(1U, failSensorList.size());
     EXPECT_EQ("Sensor threshold asserted", failSensorList["temp1"].first);
     EXPECT_EQ(failSafePercent, failSensorList["temp1"].second);
 }
@@ -349,7 +349,7 @@
 
     std::map<std::string, std::pair<std::string, double>> failSensorList =
         zone->getFailSafeSensors();
-    EXPECT_EQ(3, failSensorList.size());
+    EXPECT_EQ(3U, failSensorList.size());
     EXPECT_EQ("Sensor threshold asserted", failSensorList["temp1"].first);
     EXPECT_EQ(60, failSensorList["temp1"].second);
     EXPECT_EQ("Sensor reading bad", failSensorList["temp2"].first);