Copter: remove superfluous RETURN_TARGET_ALTTYPE_ from enum class names

Just repeats what's in the required prefix for the enum class

ArduCopter/mode.h

@@ -1104,9 +1104,9 @@ private:
 
     // return target alt type
     enum class ReturnTargetAltType {
-        RETURN_TARGET_ALTTYPE_RELATIVE = 0,
-        RETURN_TARGET_ALTTYPE_RANGEFINDER = 1,
-        RETURN_TARGET_ALTTYPE_TERRAINDATABASE = 2
+        RELATIVE = 0,
+        RANGEFINDER = 1,
+        TERRAINDATABASE = 2
     };
 
     // Loiter timer - Records how long we have been in loiter

ArduCopter/mode_rtl.cpp

@@ -434,39 +434,39 @@ void ModeRTL::compute_return_target()
     int32_t curr_alt = copter.current_loc.alt;
 
     // determine altitude type of return journey (alt-above-home, alt-above-terrain using range finder or alt-above-terrain using terrain database)
-    ReturnTargetAltType alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE;
+    ReturnTargetAltType alt_type = ReturnTargetAltType::RELATIVE;
     if (terrain_following_allowed && (get_alt_type() == RTLAltType::RTL_ALTTYPE_TERRAIN)) {
         // convert RTL_ALT_TYPE and WPNAV_RFNG_USE parameters to ReturnTargetAltType
         switch (wp_nav->get_terrain_source()) {
         case AC_WPNav::TerrainSource::TERRAIN_UNAVAILABLE:
-            alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE;
+            alt_type = ReturnTargetAltType::RELATIVE;
             AP::logger().Write_Error(LogErrorSubsystem::NAVIGATION, LogErrorCode::RTL_MISSING_RNGFND);
             gcs().send_text(MAV_SEVERITY_CRITICAL, "RTL: no terrain data, using alt-above-home");
             break;
         case AC_WPNav::TerrainSource::TERRAIN_FROM_RANGEFINDER:
-            alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RANGEFINDER;
+            alt_type = ReturnTargetAltType::RANGEFINDER;
             break;
         case AC_WPNav::TerrainSource::TERRAIN_FROM_TERRAINDATABASE:
-            alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_TERRAINDATABASE;
+            alt_type = ReturnTargetAltType::TERRAINDATABASE;
             break;
         }
     }
 
     // set curr_alt and return_target.alt from range finder
-    if (alt_type == ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RANGEFINDER) {
+    if (alt_type == ReturnTargetAltType::RANGEFINDER) {
         if (copter.get_rangefinder_height_interpolated_cm(curr_alt)) {
             // set return_target.alt
             rtl_path.return_target.set_alt_cm(MAX(curr_alt + MAX(0, g.rtl_climb_min), MAX(g.rtl_altitude, RTL_ALT_MIN)), Location::AltFrame::ABOVE_TERRAIN);
         } else {
             // fallback to relative alt and warn user
-            alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE;
+            alt_type = ReturnTargetAltType::RELATIVE;
             gcs().send_text(MAV_SEVERITY_CRITICAL, "RTL: rangefinder unhealthy, using alt-above-home");
             AP::logger().Write_Error(LogErrorSubsystem::NAVIGATION, LogErrorCode::RTL_MISSING_RNGFND);
         }
     }
 
     // set curr_alt and return_target.alt from terrain database
-    if (alt_type == ReturnTargetAltType::RETURN_TARGET_ALTTYPE_TERRAINDATABASE) {
+    if (alt_type == ReturnTargetAltType::TERRAINDATABASE) {
         // set curr_alt to current altitude above terrain
         // convert return_target.alt from an abs (above MSL) to altitude above terrain
         //   Note: the return_target may be a rally point with the alt set above the terrain alt (like the top of a building)
@@ -476,14 +476,14 @@ void ModeRTL::compute_return_target()
             curr_alt = curr_terr_alt;
         } else {
             // fallback to relative alt and warn user
-            alt_type = ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE;
+            alt_type = ReturnTargetAltType::RELATIVE;
             AP::logger().Write_Error(LogErrorSubsystem::TERRAIN, LogErrorCode::MISSING_TERRAIN_DATA);
             gcs().send_text(MAV_SEVERITY_CRITICAL, "RTL: no terrain data, using alt-above-home");
         }
     }
 
     // for the default case we must convert return-target alt (which is an absolute alt) to alt-above-home
-    if (alt_type == ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE) {
+    if (alt_type == ReturnTargetAltType::RELATIVE) {
         if (!rtl_path.return_target.change_alt_frame(Location::AltFrame::ABOVE_HOME)) {
             // this should never happen but just in case
             rtl_path.return_target.set_alt_cm(0, Location::AltFrame::ABOVE_HOME);
@@ -508,7 +508,7 @@ void ModeRTL::compute_return_target()
     }
 
     // set returned target alt to new target_alt (don't change altitude type)
-    rtl_path.return_target.set_alt_cm(target_alt, (alt_type == ReturnTargetAltType::RETURN_TARGET_ALTTYPE_RELATIVE) ? Location::AltFrame::ABOVE_HOME : Location::AltFrame::ABOVE_TERRAIN);
+    rtl_path.return_target.set_alt_cm(target_alt, (alt_type == ReturnTargetAltType::RELATIVE) ? Location::AltFrame::ABOVE_HOME : Location::AltFrame::ABOVE_TERRAIN);
 
 #if AC_FENCE == ENABLED
     // ensure not above fence altitude if alt fence is enabled