arm64: dts: allwinner: h6: Introduce Beelink GS1 board

Beelink GS1 is an Allwinner H6 based TV box,
which support:
- Allwinner H6 Quad-core 64-bit ARM Cortex-A53
- GPU Mali-T720
- 2GB LPDDR3 RAM
- AXP805 PMIC
- 1Gbps GMAC via RTL8211E
- FN-Link 6222B-SRB Wifi/BT
- 1x USB 2.0 Host and 1x USB 3.0 Host
- HDMI port
- S/PDIF Tx
- IR receiver
- 5V/2A DC power supply

Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>