Enable raspberrypi official 7 inch touchscreen

[chbae]

Is your feature request related to a problem? Please describe.
Enable raspberrypi official touchscreen

Describe the solution you'd like
To enable the touchscreen

1. Enable the touchscreen driver and add dtb
2. Change DRM path for media playback (/omx-components/src/omxdrm/OMXDrm.cpp)

Additional context
raspberrypi official 7 inch touchscreen: https://www.raspberrypi.org/products/raspberry-pi-touch-display/

[Herrie82]

@Andolamin (LG SVL) added this to LuneOS RPi 3 sometime in the past. There might be some clues in that work.