Pixhawk 2.1 and Dshot1200 ESC's

I want to use Dshot1200 ESC’s in my hexa.
I know that I have to use AUX from 1 to 6 ( need change parameter BRD_PWN_COUNT to 6) ports to connect ESC’s and Cube.
The question is that I also want to use landing gear.
Usualy landing gear is connected to AUX1…AUX4
Where can I connect landing gear and what I have to configure ?

Set the SERVOx_FUNCTION for the channel of choice (1-8 as you have motors on 9-14) to 29.