AP_Camera: correct compilation when HAL_MOUNT_SET_CAMERA_SOURCE_ENABL…

…ED not set

 - need the include because an enumeration is used in the header (relied on the include previously being made by a file including this header)
 - set_lens is not part of set-camera-source, so shouldn't be excluded
 - exclude entire method, not body of method based on the include

libraries/AP_Camera/AP_Camera_Backend.h

@@ -82,10 +82,10 @@ class AP_Camera_Backend
     // p1,p2 are in range 0 to 1.  0 is left or top, 1 is right or bottom
     virtual bool set_tracking(TrackingType tracking_type, const Vector2f& p1, const Vector2f& p2) { return false; }
 
-#if AP_CAMERA_SET_CAMERA_SOURCE_ENABLED
     // set camera lens as a value from 0 to 5
     virtual bool set_lens(uint8_t lens) { return false; }
 
+#if AP_CAMERA_SET_CAMERA_SOURCE_ENABLED
     // set_camera_source is functionally the same as set_lens except primary and secondary lenses are specified by type
     virtual bool set_camera_source(AP_Camera::CameraSource primary_source, AP_Camera::CameraSource secondary_source) { return false; }
 #endif

libraries/AP_Camera/AP_Camera_Mount.cpp

@@ -70,17 +70,17 @@ bool AP_Camera_Mount::set_lens(uint8_t lens)
     return false;
 }
 
+#if HAL_MOUNT_SET_CAMERA_SOURCE_ENABLED
 // set_camera_source is functionally the same as set_lens except primary and secondary lenses are specified by type
 bool AP_Camera_Mount::set_camera_source(AP_Camera::CameraSource primary_source, AP_Camera::CameraSource secondary_source)
 {
-#if HAL_MOUNT_SET_CAMERA_SOURCE_ENABLED
     AP_Mount* mount = AP::mount();
     if (mount != nullptr) {
         return mount->set_camera_source(get_mount_instance(), (uint8_t)primary_source, (uint8_t)secondary_source);
     }
-#endif
     return false;
 }
+#endif
 
 // send camera information message to GCS
 void AP_Camera_Mount::send_camera_information(mavlink_channel_t chan) const

libraries/AP_Camera/AP_Camera_Mount.h

@@ -22,6 +22,8 @@
 
 #if AP_CAMERA_MOUNT_ENABLED
 
+#include "AP_Camera.h"
+
 class AP_Camera_Mount : public AP_Camera_Backend
 {
 public:
@@ -54,8 +56,10 @@ class AP_Camera_Mount : public AP_Camera_Backend
     // set camera lens as a value from 0 to 5
     bool set_lens(uint8_t lens) override;
 
+#if AP_CAMERA_SET_CAMERA_SOURCE_ENABLED
     // set_camera_source is functionally the same as set_lens except primary and secondary lenses are specified by type
     bool set_camera_source(AP_Camera::CameraSource primary_source, AP_Camera::CameraSource secondary_source) override;
+#endif  // AP_CAMERA_SET_CAMERA_SOURCE_ENABLED
 
     // send camera information message to GCS
     void send_camera_information(mavlink_channel_t chan) const override;