Fixed a few C++ build warnings.

light/color_instant_handler.h

@@ -29,8 +29,6 @@ namespace bslamp2 {
 class ColorInstantHandler : public GPIOOutputs {
 public:
     bool set_light_color_values(light::LightColorValues v) {
-        GPIOOutputs *delegate;
-        
         // The actual implementation of the various light modes is in
         // separated targeted classes. These classes are called here
         // in a chain of command-like pattern, to let the first one

light/color_rgb_light.h

@@ -273,7 +273,6 @@ public:
             v.get_brightness(), &rgb_a_);
 
         // Determine duty cycle measurements for the inner ring.
-        auto level_b = ceil(level);
         set_duty_cycles_(
             &rgbp_b_, level_a, v.get_red(), v.get_green(), v.get_blue(),
             v.get_brightness(), &rgb_b_);