Remove unused errCount variables

Each derived sensor class used to maintain their own error counts until
commit 961bf09 - 'Standardize read errors' moved all read error handling
into sensor.hpp.  That commit missed removing errCount from a few of the
classes, so this one removes the rest of them.

Testing: Everything still builds.  Error counting still works correctly
in hwmontempsensor.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I021117a337281d98f92eddf6e42b197238301d65
diff --git a/include/HwmonTempSensor.hpp b/include/HwmonTempSensor.hpp
index 11e46f3..4f59af6 100644
--- a/include/HwmonTempSensor.hpp
+++ b/include/HwmonTempSensor.hpp
@@ -30,7 +30,6 @@
     boost::asio::deadline_timer waitTimer;
     boost::asio::streambuf readBuf;
     std::string path;
-    size_t errCount;
     unsigned int sensorPollMs;
 
     void handleResponse(const boost::system::error_code& err);
diff --git a/include/PSUSensor.hpp b/include/PSUSensor.hpp
index 0559073..fd69c5a 100644
--- a/include/PSUSensor.hpp
+++ b/include/PSUSensor.hpp
@@ -32,7 +32,6 @@
     std::string path;
     std::string pathRatedMax;
     std::string pathRatedMin;
-    size_t errCount;
     unsigned int sensorFactor;
     uint8_t minMaxReadCounter;
     void handleResponse(const boost::system::error_code& err);
diff --git a/include/TachSensor.hpp b/include/TachSensor.hpp
index 1b80404..fa9de07 100644
--- a/include/TachSensor.hpp
+++ b/include/TachSensor.hpp
@@ -88,7 +88,6 @@
     std::string path;
     std::optional<std::string> led;
     bool ledState = false;
-    size_t errCount;
     void setupRead(void);
     void handleResponse(const boost::system::error_code& err);
     void checkThresholds(void) override;