control_allocator: add coaxial helicopter effectiveness

It's now just a copy of the helicopter such that changes get well
visible in the history.

src/modules/control_allocator/module.yaml

@@ -29,6 +29,7 @@ parameters:
                 9: Custom
                 10: Helicopter (tail ESC)
                 11: Helicopter (tail Servo)
+                12: Helicopter (Coaxial)
             default: 0
 
         CA_METHOD:
@@ -1119,3 +1120,23 @@ mixer:
                       name: CA_HELI_YAW_CCW
                     - label: 'Throttle spoolup time'
                       name: COM_SPOOLUP_TIME
+
+            12: # Helicopter (Coaxial)
+                actuators:
+                  - actuator_type: 'motor'
+                    count: 2
+                    item_label_prefix: ['Clockwise Rotor', 'Counter-clockwise Rotor']
+                  - actuator_type: 'servo'
+                    group_label: 'Swash plate servos'
+                    count: 'CA_SP0_COUNT'
+                    per_item_parameters:
+                        extra:
+                          - name: 'CA_SP0_ANG${i}'
+                            label: 'Angle'
+                          - name: 'CA_SP0_ARM_L${i}'
+                            label: 'Arm Length (relative)'
+                          - name: 'CA_SV_CS${i}_TRIM'
+                            label: 'Trim'
+                    parameters:
+                      - label: 'Throttle spoolup time'
+                        name: COM_SPOOLUP_TIME