HDMI with 800x480

I used this config for HDMI but it's not working. It's shown black screen.

```
hdmi_group=2
hdmi_mode=87
hdmi_cvt=800 480 60 6 0 0 0
hdmi_drive=1
```

https://learn.adafruit.com/adafruit-5-800x480-tft-hdmi-monitor-touchscreen-backpack/raspberry-pi-config

Same config works well with other OS and I used the same config for LineageOS and worked there too.