rockchip: px30/rk3326: Use soc dtsi files from dts/upstream

rockchip: px30/rk3326: Use soc dtsi files from dts/upstream

The commit f087f7fd277d ("rockchip: px30/rk3326: migrate to
OF_UPSTREAM") migrated px30/rk3326 boards to use OF_UPSTREAM, however
the soc dtsi and dt-bindings files remained.

Remove the remaining px30/rk3326 soc dtsi and dt-bindings to ensure the
files from dts/upstream is used.

The gpio-ranges props is moved to u-boot.dtsi files and a ethernet0
alias is added to px30-firefly, they are missing in the dts/upstream
files. No changes are expected with this.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>