Turn on a bunch of warnings

Turn on as many warnings as easily possible from:
https://github.com/lefticus/cppbestpractices/blob/e73393f25a85f83fed7399d8b65cb117d00b2231/02-Use_the_Tools_Available.md#L100

Tested:
ipmitool sensor list still works

Change-Id: Ied8fa66de9fcd25e448f8048c4f8216b426b6f55
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/src/ChassisIntrusionSensor.cpp b/src/ChassisIntrusionSensor.cpp
index 4bf7fdc..f10e9b9 100644
--- a/src/ChassisIntrusionSensor.cpp
+++ b/src/ChassisIntrusionSensor.cpp
@@ -43,9 +43,6 @@
 // Status bit field masks
 const static constexpr size_t pchRegMaskIntrusion = 0x01;
 
-// Hold current PCH register values
-static unsigned int intrudeValue;
-
 // gpio sysfs path
 constexpr const char* gpioPath = "/sys/class/gpio/";
 
@@ -104,7 +101,7 @@
         return -1;
     }
 
-    unsigned int statusValue;
+    int statusValue;
     unsigned int statusMask = pchRegMaskIntrusion;
     unsigned int statusReg = pchStatusRegIntrusion;