rockchip: rv1108: Convert to OF_UPSTREAM

Instead of using the local rv1108 devicetree copies from U-Boot,
let's convert the rv1108 boards to OF_UPSTREAM so that the upstream kernel
devicetrees can be used instead.

Tested on a rv1108-elgin-r1 board.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Otavio Salvador <otavio@ossystems.com.br>
Tested-by: Otavio Salvador <otavio@ossystems.com.br>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/configs/elgin-rv1108_defconfig b/configs/elgin-rv1108_defconfig
index 59b88a8..454ed9e 100644
--- a/configs/elgin-rv1108_defconfig
+++ b/configs/elgin-rv1108_defconfig
@@ -6,7 +6,7 @@
 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
 CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x60100000
 CONFIG_ENV_OFFSET=0x3F8000
-CONFIG_DEFAULT_DEVICE_TREE="rv1108-elgin-r1"
+CONFIG_DEFAULT_DEVICE_TREE="rockchip/rv1108-elgin-r1"
 CONFIG_ROCKCHIP_RV1108=y
 CONFIG_ROCKCHIP_BOOT_MODE_REG=0
 CONFIG_TARGET_ELGIN_RV1108=y