i2c: add missing methods so the GrovePi fully implements the Adaptor interface

Signed-off-by: Ron Evans <ron@hybridgroup.com>

drivers/i2c/grovepi_driver.go

@@ -80,6 +80,16 @@ func (d *GrovePiDriver) Start() (err error) {
 // Halt returns true if devices is halted successfully
 func (d *GrovePiDriver) Halt() (err error) { return }
 
+// Connect is here to implement the Adaptor interface.
+func (d *GrovePiDriver) Connect() (err error) {
+	return
+}
+
+// Finalize is here to implement the Adaptor interface.
+func (d *GrovePiDriver) Finalize() (err error) {
+	return
+}
+
 // AnalogRead returns value from analog pin implementing the AnalogReader interface.
 func (d *GrovePiDriver) AnalogRead(pin string) (value int, err error) {
 	pin = getPin(pin)

drivers/i2c/grovepi_driver_test.go

@@ -21,6 +21,9 @@ var _ gpio.DigitalWriter = (*GrovePiDriver)(nil)
 // must implement the AnalogReader interface
 var _ aio.AnalogReader = (*GrovePiDriver)(nil)
 
+// must implement the Adaptor interface
+var _ gobot.Adaptor = (*GrovePiDriver)(nil)
+
 func initTestGrovePiDriver() (driver *GrovePiDriver) {
 	driver, _ = initGrovePiDriverWithStubbedAdaptor()
 	return