rockchip: rk3288: Use rk3288.dtsi from dts/upstream

rk3288.dtsi from arch/arm/dts is almost identical to the rk3288.dtsi
from dts/upstream, it differs only with a minor change in hdmi port
nodes, something that does not affect U-Boot.

Remove arch/arm/dts/rk3288.dtsi to use rk3288.dtsi from dts/upstream.
Also drop gpio aliases from -u-boot.dtsi that has been part of
rk3288.dtsi for some time.

No functional change to board DTs is intended with this removal.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

arch/arm/dts/rk3288-u-boot.dtsi

@@ -7,15 +7,6 @@
 
 / {
 	aliases {
-		gpio0 = &gpio0;
-		gpio1 = &gpio1;
-		gpio2 = &gpio2;
-		gpio3 = &gpio3;
-		gpio4 = &gpio4;
-		gpio5 = &gpio5;
-		gpio6 = &gpio6;
-		gpio7 = &gpio7;
-		gpio8 = &gpio8;
 		mmc0 = &emmc;
 		mmc1 = &sdmmc;
 		mmc2 = &sdio0;