My DTS is for a customized set of pins that works for me, and it is different than/from the waveshare set of pins.
You need to change:
* file name change to: ili9486-ads7846-spi1.dts
* gpio pin selections everywhere in the DTS
* "adafruit,yx240qv29" should be "ilitek,ili9486"
* change "rotation" to "rotate"
* change "reset-gpios = <&pio N N 0>;" to "reset-gpios = <&pio N N 1>;
Then sudo armbian-add-overlay ili9486-ads7846-spi1.dts
Reboot
(does anyone know the correct DRM driver for ili9486?)