CppCheck cleanup (#975)

* Add support for inline cppcheck suppressions
* Clean out all known cppcheck issues
* Terminate toll-gate on found cppcheck issues

drivers/AVR/DigitalIO/PinIO.h

@@ -41,6 +41,10 @@ class PinIO
 {
 public:
 	/** Create a PinIO object with no assigned pin. */
+	// Suppress warning about uninitialized variables because initializing them in an init function
+	// allows the compiler to optimize away the variables in case the class is only instantiated but
+	// never used.
+	// cppcheck-suppress uninitMemberVar
 	PinIO() : bit_(0), mask_(0XFF) {}
 	/** Constructor
 	 * @param[in] pin Pin assigned to this object.
@@ -186,4 +190,4 @@ private:
 	volatile uint8_t* portReg_;
 };
 #endif  // PinIO_h
-/** @} */
+/** @} */

drivers/AVR/DigitalIO/examples/SoftDS1307Utility/SoftDS1307Utility.ino

@@ -179,7 +179,6 @@ void dumpAll(void)
 //------------------------------------------------------------------------------
 void fillNvRam(void)
 {
-	uint8_t buf[8];
 	PgmPrint("Enter HEX value for all NV RAM locations (00-FF): ");
 	uint16_t v;
 	if (!hexRead(&v)) {
@@ -363,4 +362,4 @@ void loop(void)
 	} else {
 		PgmPrintln("Invalid option");
 	}
-}
+}