arm: davinci: Migrate da850-evm to OF_UPSTREAM

The da850-evm can remove the U-Boot device trees if migrated
to OF_UPSTREAM.  This means pointing the device trees to the
ti/davinci directory.

Signed-off-by: Adam Ford <aford173@gmail.com>

v2:  Remove DTS from Makefile.
diff --git a/configs/da850evm_defconfig b/configs/da850evm_defconfig
index 1095a76..30d1a93 100644
--- a/configs/da850evm_defconfig
+++ b/configs/da850evm_defconfig
@@ -18,7 +18,7 @@
 CONFIG_ENV_OFFSET=0x80000
 CONFIG_ENV_SECT_SIZE=0x10000
 CONFIG_DM_GPIO=y
-CONFIG_DEFAULT_DEVICE_TREE="da850-evm"
+CONFIG_DEFAULT_DEVICE_TREE="ti/davinci/da850-evm"
 CONFIG_SPL_TEXT_BASE=0x80000000
 CONFIG_SPL_SERIAL=y
 CONFIG_SPL_STACK=0x8001ff00