AP_Notify: allow pca9685 to be compiled out of code

libraries/AP_Notify/AP_Notify.cpp

@@ -307,9 +307,11 @@ void AP_Notify::add_backends(void)
                 }
                 break;
 #endif
+#if AP_NOTIFY_PCA9685_ENABLED
             case Notify_LED_PCA9685LED_I2C_External:
                 ADD_BACKEND(new PCA9685LED_I2C());
                 break;
+#endif
             case Notify_LED_NeoPixel:
                 ADD_BACKEND(new NeoPixel());
                 break;

libraries/AP_Notify/AP_Notify_config.h

@@ -16,3 +16,7 @@
 #ifndef AP_NOTIFY_NCP5623_ENABLED
 #define AP_NOTIFY_NCP5623_ENABLED 1
 #endif
+
+#ifndef AP_NOTIFY_PCA9685_ENABLED
+#define AP_NOTIFY_PCA9685_ENABLED 1
+#endif

libraries/AP_Notify/PCA9685LED_I2C.cpp

@@ -17,6 +17,8 @@
  */
 #include "PCA9685LED_I2C.h"
 
+#if AP_NOTIFY_PCA9685_ENABLED
+
 #include <AP_HAL/AP_HAL.h>
 
 #define NAVIO_LED_BRIGHT 0x0    // full brightness
@@ -110,3 +112,5 @@ void PCA9685LED_I2C::_timer(void)
 
     _dev->transfer(transaction, sizeof(transaction), nullptr, 0);
 }
+
+#endif // AP_NOTIFY_PCA9685_ENABLED

libraries/AP_Notify/PCA9685LED_I2C.h

@@ -19,6 +19,8 @@
 #include <AP_HAL/I2CDevice.h>
 #include "RGBLed.h"
 
+#if AP_NOTIFY_PCA9685_ENABLED
+
 class PCA9685LED_I2C : public RGBLed
 {
 public:
@@ -35,3 +37,5 @@ private:
     } rgb;
     bool _need_update;
 };
+
+#endif  // AP_NOTIFY_PCA9685_ENABLED